Answer with explanation:
Given two sets
A={2, 4, 6, 8} and B={2, 3, 5, 7, 9}
⇒n(S)=Cardinality of a set
Means the number of distinct elements in a Set is called it's cardinal number.
→In Set A,total number of distinct elements is 4.
n(A)=4
ESTIMATE THE ANSWER BY ROUNDING EACH NUMBER TO THE NEAREST 10. 961 + 27.8 + 693.0 + 573 +76.4 =
Answer:
2330
Step-by-step explanation:
In rounding nearest 10,
If the ones place digit is 5 or more then 5 then we round the number to upper 10, while if the ones place digit is less than 5 then we round the number to lower 10,
For example : 34 ≈ 30 while 36 ≈ 40,
Now, given expression,
961 + 27.8 + 693.0 + 573 +76.4
By the above statement 961≈ 960, 27.8 ≈ 30, 693.0 ≈ 690, 573 ≈ 570 and 76.4 ≈ 80,
Hence, 961 + 27.8 + 693.0 + 573 +76.4 = 960 + 30 + 690 + 570 + 80 = 2330.
Answer:
2330
Step-by-step explanation:
961 + 27.8 + 693.0 + 573 +76.4 =
Rounding to the nearest 10
960 + 30 + 690 + 570 + 80
2330
1. Let a; b; c; d; n belong to Z with n > 0. Suppose a congruent b (mod n) and c congruent d (mod n). Use the definition
of congruence to
(a) prove that a + c congruent b + d (mod n).
(b) prove that ac congruent bd (mod n).
Expert Answer
Answer:
Proofs are in the explantion.
Step-by-step explanation:
We are given the following:
1) [tex]a \equi b (mod n) \rightarrow a-b=kn[/tex] for integer [tex]k[/tex].
1) [tex] c \equi d (mod n) \rightarrow c-d=mn[/tex] for integer [tex]m[/tex].
a)
Proof:
We want to show [tex]a+c \equiv b+d (mod n)[/tex].
So we have the two equations:
a-b=kn and c-d=mn and we want to show for some integer r that we have
(a+c)-(b+d)=rn. If we do that we would have shown that [tex]a+c \equiv b+d (mod n)[/tex].
kn+mn = (a-b)+(c-d)
(k+m)n = a-b+ c-d
(k+m)n = (a+c)+(-b-d)
(k+m)n = (a+c)-(b+d)
k+m is is just an integer
So we found integer r such that (a+c)-(b+d)=rn.
Therefore, [tex]a+c \equiv b+d (mod n)[/tex].
//
b) Proof:
We want to show [tex]ac \equiv bd (mod n)[/tex].
So we have the two equations:
a-b=kn and c-d=mn and we want to show for some integer r that we have
(ac)-(bd)=tn. If we do that we would have shown that [tex]ac \equiv bd (mod n)[/tex].
If a-b=kn, then a=b+kn.
If c-d=mn, then c=d+mn.
ac-bd = (b+kn)(d+mn)-bd
= bd+bmn+dkn+kmn^2-bd
= bmn+dkn+kmn^2
= n(bm+dk+kmn)
So the integer t such that (ac)-(bd)=tn is bm+dk+kmn.
Therefore, [tex]ac \equiv bd (mod n)[/tex].
//
certain electronics manufacturer found that the marginal cost C to produce x DVD/Blu- ray players can be found using the equation C = 0.03 x 2 − 8 x + 700 . If the marginal cost were $522, how many DVD/Blu-ray players were produced?
Answer:
242.
Step-by-step explanation:
C = 0.03 x 2 − 8 x + 700
When the marginal cost = $522 we have:
522 = 0.03 x 2 − 8 x + 700
0.03x^2 - 8x + 700 - 522 = 0
0.03x^2 - 8x + 178 = 0
Using the quadratic formula:
x = [ -(-8) +/- sqrt( 64 - 4 * 0.03 * 178)] / 0.06
= 8 +/- sqrt42.64 / 0.06
= 242 players.
242 DVD/Blu-ray players were produced
Marginal cost is the change in cost as a result of producing additional number of units.
Given that the marginal cost is:
C = 0.03x² - 8x + 700
Therefore for a marginal cost of $522, the number of DVD players is:
522 = 0.03x² - 8x + 700
0.03x² - 8x + 178 = 0
x = 24 and x = 242
Therefore 242 DVD/Blu-ray players were produced
Find out more at: https://brainly.com/question/7781429
How many integers between 10000 and 99999, inclusive, are divisible by 3 or
5 or 7?
Answer: Hence, there are approximately 48884 integers are divisible by 3 or 5 or 7.
Step-by-step explanation:
Since we have given that
Integers between 10000 and 99999 = 99999-10000+1=90000
n( divisible by 3) = [tex]\dfrac{90000}{3}=30000[/tex]
n( divisible by 5) = [tex]\dfrac{90000}{5}=18000[/tex]
n( divisible by 7) = [tex]\dfrac{90000}{7}=12857.14[/tex]
n( divisible by 3 and 5) = n(3∩5)=[tex]\dfrac{90000}{15}=6000[/tex]
n( divisible by 5 and 7) = n(5∩7) = [tex]\dfrac{90000}{35}=2571.42[/tex]
n( divisible by 3 and 7) = n(3∩7) = [tex]\dfrac{90000}{21}=4285.71[/tex]
n( divisible by 3,5 and 7) = n(3∩5∩7) = [tex]\dfrac{90000}{105}=857.14[/tex]
As we know the formula,
n(3∪5∪7)=n(3)+n(5)+n(7)-n(3∩5)-n(5∩7)-n(3∩7)+n(3∩5∩7)
[tex]=30000+18000+12857.14-6000-2571.42-4258.71+857.14\\\\=48884.15[/tex]
Hence, there are approximately 48884 integers are divisible by 3 or 5 or 7.
The area under the normal curve between the mean and a score for which z= - 1.20 is
a. .2563
b. .7563
c. .1138
d. .3862
e. .3849
Answer: e. 0.3849
Step-by-step explanation:
We know that the mean lies exactly at the middle of the normal curve .
The z-score of the mean value is 0.
Also According to the standard normal probability table, the probability value of z=0 is P(z<0)=0.5.
And the probability value of z=-1.20 is P(z<-1.2) =0.1150697.
Now, the area under the normal curve between the mean and a score for which z= - 1.20 is given by :-
[tex]P(z<0)-P(z<-1.2)=0.5-0.1150697=0.3849303\approx0.3849[/tex]
Hence, the area under the normal curve between the mean and a score for which z= - 1.20 is 0.3849 .
Which is relatively better: a score of 87 on a psychology test or a score of 52 on an economics test? Scores on the psychology test have a mean of 92 and a standard deviation of 5. Scores on the economics test have a mean of 62 and a standard deviation of 6.
Answer: Psychology test score is relatively better than economics test score.
Step-by-step explanation:
For this question, we are using Z-score to compare the psychology test score and economics test score.
Z-scores are an approach to compare results from a test with a "normal" population.
Z = [tex]\frac{X - u}{S.D}[/tex]
where,
X - Test score
u - Mean
S.D - Standard deviation
Psychology Test:
Z = [tex]\frac{87 - 92}{5}[/tex]
= [tex]\frac{-5}{5}[/tex]
= -1
Economics Test:
Z = [tex]\frac{52 - 62}{6}[/tex]
= [tex]\frac{-10}{6}[/tex]
= -1.6
Hence, above calculation shows that z- score for pshychology test is greater than the z- score for economics test. so, psychology test score is better than economics test score.
To determine which score is relatively better, we need to use the concept of z-scores, which measure how many standard deviations a particular score is from the mean.
Explanation:To determine which score is relatively better, we need to use the concept of z-scores, which measure how many standard deviations a particular score is from the mean. The formula for calculating the z-score is:
z = (X - μ) / σ
where X is the score, μ is the mean, and σ is the standard deviation.
For the 87 on the psychology test:
z = (87 - 92) / 5 = -1
For the 52 on the economics test:
z = (52 - 62) / 6 = -1.67
Since a higher z-score indicates a score that is relatively better, we can conclude that the score of 87 on the psychology test is relatively better than the score of 52 on the economics test.
The equation of a circle is given below. Identify the radius and center.
x^2 + y^2 + 6x -8y +21 = 0
[tex](x-a)^2+(y-b)^2=r^2[/tex]
center - [tex](a,b)[/tex]
[tex]x^2 + y^2 + 6x -8y +21 = 0 \\x^2+6x+9+y^2-8y+16-4=0\\(x+3)^2+(y-4)^2=4[/tex]
center - [tex](-3,4)[/tex]
[tex]r=2[/tex]
Answer:
The center is: [tex](-3, 4)[/tex] and the radius is [tex]r=2[/tex]
Step-by-step explanation:
The general equation of a circle has the following formula:
[tex](x-h)^2 + (y-k)^2 = r^2\\[/tex]
Where r is the radius of the circle and (h, k) is the center of the circle
In this case we have the following equation
[tex]x^2 + y^2 + 6x -8y +21 = 0[/tex]
To find the radius and the center of this cicunference we must rewrite the equation in the general form of a circumference completing the Square
[tex](x^2 + 6x)+ (y^2 -8y) +21 = 0\\\\(x^2 + 6x+9)+ (y^2 -8y+16) +21 = 9+16\\\\(x^2 + 6x+9)+ (y^2 -8y+16) = 9+16-21\\\\(x+3)^2+ (y-4)^2 = 4\\\\(x+3)^2+ (y-4)^2 = 2^2[/tex]
Then the center is: [tex](-3, 4)[/tex] and the radius is [tex]r=2[/tex]
|3 - 10| - (12/4 +2)^2
Answer:
-18
Step-by-step explanation:
Simplify the following:
abs(3 - 10) - (12/4 + 2)^2
The gcd of 12 and 4 is 4, so 12/4 = (4×3)/(4×1) = 4/4×3 = 3:
abs(3 - 10) - (3 + 2)^2
3 + 2 = 5:
abs(3 - 10) - 5^2
3 - 10 = -7:
abs(-7) - 5^2
5^2 = 25:
abs(-7) - 25
Since -7<=0, then abs(-7) = 7:
7 - 25
7 - 25 = -18:
Answer: -18
For this case we must resolve the expression:
[tex]| 3-10 | - (\frac {12} {4}+2) ^ 2[/tex]
We have the following definitions:
Different signs are subtracted and the sign of the major is placed.
Absolute value definition:[tex]| -a | = a[/tex]
Resolving we have:
[tex]| 3-10 | = | -7 | = 7[/tex]
[tex](\frac {12} {4}+2) ^ 2 = (3+2) ^ 2 = 5 ^ 2 = 25[/tex]
Then, rewriting the expression:
[tex]7-25 = -18[/tex]
Answer:
-18
this is formula manipulation, I'd appreciate if the steps were provided. only respond if you know how to get the answer, thank you
Answer:
r = 3V/(2πh²)h = 3V/b²r = 25/π cm ≈ 7.9577 cmw = 15 cmStep-by-step explanation:
1. Multiply both sides of the equation by the reciprocal of the coefficient of r.
[tex]V\cdot\dfrac{3}{2\pi h^2}=r\\\\r=\dfrac{3V}{2\pi h^2}[/tex]
__
2. Multiply both sides of the equation by the reciprocal of the coefficient of h.
[tex]V\cdot\dfrac{3}{b^2}=h\\\\h=\dfrac{3V}{b^2}[/tex]
__
3. Solve the circumference formula for r, then substitute the given information.
[tex]C=2\pi r\\\\r=\dfrac{C}{2\pi}\qquad\text{divide by the coefficient of r}\\\\r=\dfrac{50\,\text{cm}}{2\pi}=\dfrac{25}{\pi}\,\text{cm}\approx 7.9577\,\text{cm}[/tex]
__
4. Solve the perimeter formula for width, the substitute the given information and do the arithmetic.
[tex]P=2(L+W)\\\\\dfrac{P}{2}=L+W\qquad\text{divide by 2}\\\\\dfrac{P}{2}-L=W\qquad\text{subtract L}\\\\\dfrac{40\,\text{cm}}{2}-5\,\text{cm}=W=15\,\text{cm}[/tex]
_____
In general, solving for a particular variable involves "undoing" what has been done to the variable, usually in the reverse order. In part 4, the variable W has L added and the sum is multiplied by 2. We "undo" those operations, last operation first, by dividing by 2 and subtracting L.
The properties of equality say you can do what you like to an equation as long as you do the same thing to both sides of the equation. So, when we say "divide by 2", we mean "divide both sides of the equation by 2." Likewise, "subtract L" means "subtract L from both sides of the equation."
HELP! Need quick - Determine whether the data distribution appears to be positively skewed, negatively skewed, or symmetric.
The table below shows the average employee salary (in thousands) at S&S, Inc for the last five years.
A) negatively skewed
B) symmetric
C) positively skewed
Answer:
A. negatively skewed
Step-by-step explanation:
Plot the values of salary against years
You will notice that;
The graph has a long left tailThe tail is longer towards the negative direction of the number lineThis mean that this graph is a negative skewed graph/left-skewed distribution
In the attached sketch of the plot, join the points with a smooth curve and observe the above mentioned properties.
The x-axis scale ranges from 2000 to 2015 where 0=2000, 1=2001,2=2002......,15=2015
Hope this will give you a visual picture of the negatively- skewed distribution
According to a published study, 13% of men has been involved in a minor traffic accident. Suppose we have randomly and independently sampled 400 and asked each whether he has been involved in a minor traffic accident. How many of the sampled men do we expect to have been involved in a minor traffic accident?
Answer: There are 52 men we can expect to have been involved in a minor traffic accident.
Step-by-step explanation:
Since we have given that
Percentage of men has been involved in a minor traffic accident = 13%
Number of men surveyed = 400
So, Number of sample men we can expect to have been involved in a minor traffic accident is given by
[tex]\dfrac{13}{100}\times 400\\\\=0.13\times 400\\\\=52[/tex]
Hence, there are 52 men we can expect to have been involved in a minor traffic accident.
You sell tickets at school for fundraisers. You sold car wash tickets, silly string fight tickets and dance tickets – for a total of 380 tickets sold. The car wash tickets were $5 each, the silly sting fight tickets were $3 each and the dance tickets were $10 each. If you sold twice as many silly string tickets as car wash tickets, and you have $1460 total, how many dance tickets were sold?
Answer:
11 dance tickets were sold. ( approx )
Step-by-step explanation:
Let x represents the number of car wash tickets, y represents the number of silly string fight tickets and z represents number of dance tickets,
Total tickets = 380,
⇒ x + y + z = 380 -----(1),
The car wash tickets were $5 each, the silly string fight tickets were $3 each and the dance tickets were $10 each, also total cost is $1460,
⇒ 5x + 3y + 10z = 1460 ----(2)
Also, there are twice as many silly string tickets as car wash tickets,
⇒ y = 2x -----(3)
From equation (1) and (2),
x + 2x + z = 380 ⇒ 3x + z = 380 -----(4)
5x + 3(2x) + 10z = 1460 ⇒ 11x + 10z = 1460 ------(5)
For finding the value of z,
3 × equation (5) - 11 × equation (4),
We get,
30z - 11z = 4380 - 4180
19z = 200
z = 10.5263157895 ≈ 11
Hence, 11 dance tickets were sold.
Consider the set of differences, denoted with d, between two dependent sets: 84, 85, 83, 63, 61, 100, 98. Find the sample standard deviation sd and round it to the nearest tenth.
Answer:
The sample standard deviation is 15.3.
Step-by-step explanation:
Given data items,
84, 85, 83, 63, 61, 100, 98,
Number of data items, N = 7,
Let x represents the data item,
Mean of the data points,
[tex]\bar{x}=\frac{84+85+83+63+61+100+98}{7}[/tex]
[tex]=82[/tex]
Hence, sample standard deviation would be,
[tex]\sigma= \sqrt{\frac{1}{N-1}\sum_{i=1}^{N} (x_i-\bar{x})^2}[/tex]
[tex]=\sqrt{\frac{1}{6}\sum_{i=1}^{7} (x_i-82)^2}[/tex]
[tex]=\sqrt{\frac{1}{6}\times 1396}[/tex]
[tex]=\sqrt{232.666666667}[/tex]
[tex]=15.2534149182[/tex]
[tex]\approx 15.3[/tex]
The sample standard deviation of the dataset: 84, 85, 83, 63, 61, 100, 98 is approximately 15.3 when rounded to the nearest tenth.
Explanation:To find the sample standard deviation of the given set, we first need to calculate the mean of the data set. Then, each number in the data set should be subtracted from the mean, and the results squared. These squared differences should be summed and divided by the number of data values minus one, which gives the variance. Taking the square root of the variance gives the sample standard deviation.
Let's do this step by step for the given dataset: 84, 85, 83, 63, 61, 100, 98.
Find the mean (average): (84+85+83+63+61+100+98) / 7 = 82 Subtract the mean from each number and square the result: (84-82)^2, (85-82)^2, ..., (98-82)^2. Sum these squared differences: 4+9+1+361+441+324+256 = 1396. Divide this sum by the number of data values minus one (n - 1): 1396 / (7 - 1) = 232.67 (This is the variance). Take the square root of the variance to get the sample standard deviation: √232.67 = 15.3 (rounded to the nearest tenth). Learn more about Sample Standard Deviation here:https://brainly.com/question/30952578
#SPJ3
Find the volume of the prism.
The correct option is B.
Any prism volume is V = BH where B is an area of the base and H is the height of the prism, so find the area of the base by B = 1/2 h(b1+b2), then multiply by the height of the prism.
How to Find the volume of the prism?
The triangles on the two ends are congruent.
So, to find the prism area, it is enough to take the area of one of the triangles and multiply it by the prism depth, which is 20 units.
Use the Pythagorean theorem to find the height of the triangle.
5^2 - 3^2 = 4^2, so the height is 4.
Multiply half times height times base: 1/2 x 4 x 3 = 6.
Multiply that by the depth, 20.
6x20=120 units^3.
Learn more about prisms on : https://brainly.com/question/21606564
#SPJ2
Find a bijection from (0,1] to (0,1)
Math: Analysis and proof
Answer with explanation:
The meaning of bijection for two sets X and Y is each and every element of X is uniquely related with element of set Y and when you take the inverse mapping every element of set Y is uniquely related with each and every element of Set X.
The two sets given are
X=(0,1]---------Semi open or Semi closed Set
Y=(0,1)---------Closed set
Between any two real numbers there are infinite number of real numbers.So cardinal number of both the sets is infinite.
There can be infinite bijection between these two sets as both sets have infinite number of elements.
X Y
0.1 ------------- 0.01
0.2 ------- 0.02
0.3 -------- 0.03
0.4 --------- 0.04
-------------------------
------------------------------
-------------------------------
--------------------------------------
One example of a bijection from [tex]\((0,1]\) to \((0,1)\)[/tex] is the function [tex]\(f(x) = \frac{x}{1 + x}\)[/tex]. This function is injective (one-to-one) and surjective (onto), making it a bijection.
To establish a bijection from [tex]\((0,1]\) to \((0,1)\)[/tex], consider the function [tex]\(f(x) = \frac{x}{1 + x}\).[/tex]
1. Injectivity (One-to-One): Assume [tex]\(f(x_1) = f(x_2)\)[/tex] for some [tex]\(x_1, x_2 \in (0,1]\)[/tex]. By solving the equation [tex]\(\frac{x_1}{1 + x_1} = \frac{x_2}{1 + x_2}\)[/tex], you find [tex]\(x_1 = x_2\)[/tex], showing that distinct elements in the domain map to distinct elements in the codomain.
2. Surjectivity (Onto): For any y in the codomain [tex]\((0,1)\)[/tex], solve [tex]\(f(x) = y\) for \(x\)[/tex]. This results in [tex]\(x = \frac{y}{1 - y}\)[/tex], which is well-defined for [tex]\(y \in (0,1)\)[/tex]. Therefore, every element in the codomain has a preimage in the domain.
Hence, [tex]\(f(x)\)[/tex] is a bijection from [tex]\((0,1]\) to \((0,1)\)[/tex].
Pretend you're playing a carnival game and you've won the lottery, sort of. You have the opportunity to select five bills from a money bag, while blindfolded. The bill values are $1, $2, $5, $10, $20, $50, and $100. How many different possible ways can you choose the five bills? (Order doesn't matter, and there are at least five of each type of bill.) A. 56 B. 120 C. 288 D. 462
Answer: 462
Step-by-step explanation:
The general theorem of combination says that there are [tex]C(n+r-1, r)[/tex], with r-combinations from a set having n elements when repetition of elements is allowed.
Here the number of denomination: [tex]n = 7[/tex] , r =5
Also order doesn't matters.
Then the number of different possible ways can you choose the five bills is given by :-[tex]C(7+5-1, 5)= C(11,5)\\\\=\dfrac{11!}{5!(11-5)!}\\\\=462[/tex]
Hence, the number of different possible ways can you choose the five bills is 462.
Determine whether the series is convergent or divergent. Hint: First use partial fraction decomposition. ∞ 8 (n−1)(n+1) n = 3 convergent divergent Correct: Your answer is correct. If it is convergent, find its sum. (If the quantity diverges, enter DIVERGES.)
I guess the series is
[tex]\displaystyle\sum_{n=3}^\infty\frac8{(n-1)(n+1)}[/tex]
Splitting into partial fractions gives
[tex]\dfrac8{(n-1)(n+1)}=\dfrac4{n-1}-\dfrac4{n+1}[/tex]
The series telescopes, which we can see by considering the [tex]k[/tex]-th partial sum:
[tex]\displaystyle\sum_{n=3}^k\frac8{(n-1)(n+1)}=(2-1)+\left(\frac43-\frac45\right)+\cdots+\left(\frac4{k-2}-\frac4k\right)+\left(\frac4{k-1}-\frac4{k+1}\right)[/tex]
(feel free to write out more terms to convince yourself that the following is true)
[tex]\displaystyle\sum_{n=3}^k\frac8{(n-1)(n+1)}=2+\frac43-\frac4k-\frac4{k+1}[/tex]
Then as [tex]k\to\infty[/tex], we end up with
[tex]\displaystyle\lim_{k\to\infty}\sum_{n=3}^k\frac8{(n-1)(n+1)}=\boxed{\frac{10}3}[/tex]
The series is convergent with a sum of -1.143
Explanation:The given series is:
∞ 8 (n-1)(n+1) / n = 3
First, we can use partial fraction decomposition to simplify the series. Factoring (n-1)(n+1) gives us [tex]n^2[/tex] - 1. So, the series becomes:
∞ 8 ([tex]n^2[/tex] - 1) / n = 3
Next, we can rewrite the series as two separate series:
∞ 8 [tex]n^2[/tex] / n - 8 / n = 3
Simplifying each series:
∞ 8n - 8 / n = 8∞ n³ - 1∞
The first series is a geometric series with a common ratio of 8 and a first term of 8. Using the formula for the sum of a geometric series, we can find its sum:
S = a / (1-r)
Substituting the values:
S = 8 / (1-8) = 8 / -7 = -1.143
Therefore, the series is convergent, and its sum is -1.143.
Learn more about Series convergence here:https://brainly.com/question/33953891
#SPJ2
g Use the properties of the natural logarithm to rewrite each logarithmic expression as an expression with a single logarithm. a . ln ( x + 5 ) − ln ( x − 5 ) = b . ln ( x + 5 ) + ln ( x − 5 )
Answer:
Given:
(a.) ㏑( x + 5 ) − ㏑( x − 5 )
(b.) ㏑( x + 5 ) + ㏑( x − 5 )
To compute the above expression, we'll use the properties of natural logarithm. i.e.
㏑(a) − ㏑(b) = ㏑[tex]\frac{a}{b}[/tex]
∴ ㏑( x + 5 ) − ㏑( x − 5 ) = ㏑[tex]\frac{x+5}{x-5}[/tex]
Similarly
㏑(a) + ㏑(b) = ㏑[tex](a\times b)[/tex]
∴ ㏑( x + 5 ) + ㏑( x − 5 ) = ㏑([tex]x^{2}[/tex]-25)
3. (6 points) Determine whether the relation R on the set A is an equivalence relation a. (3 pts) A = {1,2,3,4, 5) R={(1,1), (1,2), (1,3), (2,2), (2,3), (3,1), (3,2), (3,3), (4,4), (5,5) OPC b. (3 pts) A = {a, b, c R={(a, a), (a, c), (b, b), (c, a), (c, c)}
Answer:
a is not an equivalence relation.
b is an equivalence relation.
Step-by-step explanation:
a.
A = {1,2,3,4, 5) R={(1,1), (1,2), (1,3), (2,2), (2,3), (3,1), (3,2), (3,3), (4,4), (5,5)
To see if is an equivalence relation you need to see if you have these 3 things:
Part 1: xRx for all x in A. This is the reflexive property.
Do we? Yes we have all these points in R: (1,1), (2,2) ,(3,3) ,(4,4), and (5,5).
Part 2: If xRy then yRx. This is the symmetic property.
Do we? We have (1,2) but not (2,1). So it isn't symmetric.
Part 3: If xRy and yRz then xRz.
Do we? We are not going to check this because there is no point. We have to have all 3 parts fot it be an equivalence relation.
b.
A = {a, b, c} R={(a, a), (a, c), (b, b), (c, a), (c, c)}
To see if is an equivalence relation you need to see if you have these 3 things:
Part 1: xRx for all x in A. This is the reflexive property.
Do we? Yes we have all these points in R: (a,a),(b,b), and (c,c).
Part 2: If xRy then yRx. This is the symmetric property.
Do we? We have (a,c) and (c,a). We don't need to worry about any other (x,y) since there are no more with x and y being different. This is symmetric.
Part 3: If xRy and yRz then xRz.
Do we? We do have (a,c), (c,a), and (a,a).
We do have (c,a), (a,c), and (c,c).
So it is transitive.
Question b has all 3 parts so it is an equivalence relation.
State the domain and the range of each relation. Then determine whether the relation is a function.
(4,23)
(3,-2)
(-6,5)
(4,6)
Answer:
[tex]Domain:[/tex]{[tex]-6,3,4[/tex]}
[tex]Range:[/tex]{[tex]-2,5,6,23[/tex]}
The relation is not a function.
Step-by-step explanation:
By definition, a relation is a function if each input value has only one output value.
Given the relation:
(4,23)
(3,-2)
(-6,5)
(4,6)
The domain is the set of the x-coordinates of each ordered pair (You do not need to write 4 twice):
[tex]Domain:[/tex]{[tex]-6,3,4[/tex]}
The range is the set of the y-coordinates of each ordered pair :
[tex]Range:[/tex]{[tex]-2,5,6,23[/tex]}
Since the input value 4 has two different output values (23 and 6), the relation is not a function.
Answer:
See below.
Step-by-step explanation:
The Domain = {-6, 3, 4}.
The Range = {-2, 5, 6, 23}.
The relation is NOT a function because 4 in the domain maps to 6 and 23. In a function an element in the domain must map to one element only in the range.
The brain volumes (cm cubed ) of 20 brains have a mean of 1053.5 cm cubed and a standard deviation of 122.3 cm cubed . Use the given standard deviation and the range rule of thumb to identify the limits separating values that are significantly low or significantly high. For such data, would a brain volume of 1248.1 cm cubed be significantly high?
Answer:
2.3775
Step-by-step explanation:
M1Q5.) Enter your answer as a fully reduced fraction.
Answer:
9/17
Step-by-step explanation:
Chance of being over 40:
[tex] \frac{20 + 30 + 35}{255} = \frac{1}{3} [/tex]
Chance of drinking
root beer:
[tex] \frac{25 + 20 + 30}{255} = \frac{75}{255} [/tex]
Chance of drinking root beer and being over 40
[tex] \frac{1}{3} \times \frac{75}{255} = \frac{25}{255} [/tex]
Chance of drinking root beer OR being over 40
[tex] \frac{1}{3} + \frac{75}{255} - \frac{25}{255} = \frac{135}{255} = \frac{9}{17} [/tex]
20+30+35/255
1/3 chance of being 40+ years old
20+25+30/255
75/255 chance of drinking root beer
75/255 * 1/3
25/255 chance of drinking root beer being 40+ years old
75/255 - 25/255 * 1/3
135/255
9/17 chance of drinking root beer under the age of 40 years old.
Best of Luck!
A fluid has density 810 kg/m3 and flows with velocity v = z i + y2 j + x2 k, where x, y, and z are measured in meters and the components of v in meters per second. Find the rate of flow outward through the cylinder x2 + y2 = 9, 0 ≤ z ≤ 4.
To find the outward flow through the cylinder [tex]\(x^2 + y^2 = 4\), \(0 \leq z \leq 4\),[/tex] integrate the dot product of velocity and surface normal. The outward flux is [tex]\(810 \times 32 \pi\).[/tex]
To calculate the rate of flow outward through the cylinder [tex]\(x^2 + y^2 = 4\), \(0 \leq z \leq 4\),[/tex] let's compute the flux of the given vector field through the cylindrical surface. The outward flux through a closed surface is given by:
[tex]\[\Phi = \int_S \mathb{v} \cdot \mathb{dS}.\][/tex]
Surface Parameterization and Surface Normal.
The cylinder has radius r = 2, so the general parameterization is:
- [tex]\(x = 2 \cos(\theta)\),[/tex]
- [tex]\(y = 2 \sin(\theta)\),[/tex]
- z = z,
where [tex]\(0 \leq \theta \leq 2\pi\) and \(0 \leq z \leq 4\).[/tex]
The outward normal for the cylindrical surface is [tex]\(\mathb{n} = \cos(\theta) \mathb{i} + \sin(\theta) \mathb{j}\).[/tex]
The differential surface element is:
[tex]\[\mathb{dS} = 2 \, d\theta \, dz \, (\cos(\theta) \mathb{i} + \sin(\theta) \mathb{j}).\][/tex]
Dot Product of Velocity and Normal :
The given velocity field is:
[tex]\[\mathb{v} = z \mathb{i} + y^2 \mathb{j} + x^2 \mathb{k}.\][/tex]
The dot product of the velocity with the surface normal is:
[tex]\[\mathb{v} \cdot \mathb{dS} = 2 \, dz \, d\theta \, (z \cos(\theta) + (4 \sin^2(\theta)) \sin(\theta)).\][/tex]
Integrate to Find the Flux :
The flux through the cylindrical surface is given by:
[tex]\[\int_0^4 \int_0^{2\pi} 2 \, (z \cos(\theta) + 4 \sin^2(\theta)) \, dz \, d\theta,[/tex]
Separate and compute the integral:
- The integral of [tex]\(z \cos(\theta)\)[/tex] over[tex]\((0, 2\pi)\)[/tex] is zero (because [tex]\(\cos(\theta)\)[/tex] has symmetric oscillations).
- The integral of [tex]\(4 \sin^2(\theta)\) over \((0, 2\pi)\) is \(2\pi \cdot 4\),[/tex] since [tex]\(\sin^2(\theta) = \frac{1}{2}(1 - \cos(2\theta))\).[/tex]
This results in [tex]\(8\pi\).[/tex]
To compute the flux, multiply by 4 : [tex]\[8\pi \times 4 = 32\pi.\][/tex]
Since the density of the fluid is 810 kg/m³, the outward flux of the fluid through the cylinder, considering the density, is : [tex]\[810 \times 32 \pi.[/tex]
This would be the answer, with the expression [tex]\(810 \times 32 \pi\)[/tex] giving the rate of flow outward through the cylinder.
Complete question : A fluid has density 810 kg/m3 and flows with velocity v = z i + y2 j + x2 k, where x, y, and z are measured in meters and the components of v in meters per second. Find the rate of flow outward through the cylinder x2 + y2 = 4, 0 ≤ z ≤ 4.
"The average starting salary of individuals with a master's degree in statistics is normally distributed with a mean of $48,000 and a standard deviation of $6,000. What is the probability that a randomly selected individual with a master's in statistics will get a starting salary of at least $55,000?
Answer:
12.1%
Step-by-step explanation:
First calculate the z-score:
z = (x − μ) / σ
z = (55000 − 48000) / 6000
z = 1.17
Look up in a z-score table.
P(z>1.17) = 1 − 0.8790
P(z>1.17) = 0.1210
There's a 12.1% probability that a randomly selected individual with a master's in statistics will have a starting salary of at least $55,000.
The probability that a randomly selected individual with a Master's in statistics will get a starting salary of at least $55,000 is 12.17%.
Explanation:The problem you're dealing with involves the normal distribution which is a type of continuous probability distribution for a real-valued random variable. Given that we have a mean (μ) of $48,000, and a standard deviation (σ) of $6,000, we are asked to find the probability that a randomly selected individual with a master's in statistics will get a starting salary of at least $55,000.
This involves calculating a 'Z-score', which tells us how many standard deviations an element is from the mean. To find it, you would subtract the mean from the value of interest and divide by the standard deviation.
So, in this case, the Z-score would be: Z = (55000 - 48000) / 6000 = 1.167. Using standard Z-score tables, this corresponds to a probability of 0.8783.
However, as we are interested in the probability of a salary being at least $55,000, we need to subtract this value from 1 to get the final probability. So, the answer is: 1 - 0.8783 = 0.1217 or 12.17%.
Learn more about Probability here:https://brainly.com/question/22962752
#SPJ11
A computer password system requires 6 DIFFERENT letters (case sensitive) from the 26 alphabets. For example, AAAAAA and aaaaaa are two different passwords. Is this a PERMUTATION or a COMBINATION problem? How many passwords can be created?
Answer: 325
Step-by-step explanation:
Combination is a way to calculate the total outcomes of an event where order of the outcomes does not matter where as a Permutation is a way of arranging the elements of a set into a order or a sequence . Here order matters.
If we want to create password with 6 different letters then order matters.
Hence, we use permutations.
The number of passwords created is given by :-
[tex]^{26}P_6=\dfrac{26!}{2!(26-2)!}\\\\=\dfrac{26\times25\times24!}{2\times24!}=325[/tex]
Hence, the number of passwords created = 325
What is the probability of an event that is impossible? Suppose that a probability is approximated to be zero based on empirical results. Does this mean that the event is impossible?
Answer:
The answer is 0 and no.
Step-by-step explanation:
Consider the provided information.
If the event is impossible then the probability of that event will be 0.
Now, consider the statement 'Suppose that a probability is approximated to be zero-based on empirical results.'
Empirical probability is based on observations and if you do more observation then the probability of an event might be increased.
Thus, this means that the event is not impossible.
Answer:
THE ANSWER IS WHAT THE GUY ABOVE ME SAID....0
Step-by-step explanation:
The length of a rectangle exceeds its width by 8 inches. The perimeter is 80 inches. Find the length and the width of the rectangle.
Answer:
The width is 16 inches while the length is 24 inches.
Step-by-step explanation:
We are given that the length (L) is 8 more than it's width (W).
The equation for this is: L=8+W.
We are given the perimeter is 80.
The equation for this is 2L+2W=80.
Each term here is even so I'm going to divide both sides by 2: L+W=40.
My system to solve is:
L=8+W
L+W=40
I'm going to plug the first equation into the second giving me:
(8+W)+W=40
Drop the (), don't really need:
8+W+W=40
Combine like terms:
8+2W=40
Subtract 8 on both sides:
2W=32
Divide both sides by 2:
W=32/2
Simplify:
W=16
So if W=16 and L=8+W then L=8+16=24.
The width is 16 inches while the length is 24 inches.
Perimeter is the sum of the length of the sides used to make the given figure. The length and the width of the rectangle are 24 inches and 16 inches, respectively.
What is the perimeter?Perimeter is the sum of the length of the sides used to make the given figure.
Let the width of the rectangle be represented by x.
Given that the length of a rectangle exceeds its width by 8 inches. Therefore, the length and the width of a rectangle can be written as,
Width = x inches
Length = x inches + 8 inches
Now, as it is given that the perimeter of the rectangle is 80 inches. Therefore, the perimeter of the given rectangle can be written as,
Perimeter of rectangle = 2(Length + Width)
80 inches = 2[(x+8) + x]
80 = 2(x + 8 + x)
80 = 2(2x + 8)
80/2 = 2x + 8
40 = 2x + 8
40 - 8 = 2x
32 = 2x
x = 32/2
x = 16 inches
Further, the length and the width of the rectangle can be written as,
Width = x = 16 inches
Length = x + 8 = 16 + 8 = 24 inches
Hence, the length and the width of the rectangle are 24 inches and 16 inches, respectively.
Learn more about perimeter here:
https://brainly.com/question/10466285
#SPJ5
Two points on L1 and two points on L2 are given. Use the slope formula to determine if lines L1 and L2 are parallel, perpendicular, or neither.
L1: (1, 10) and (-1, 7)
L2: (0, 3) and (1, 5 )
Answer:
The lines L1 and L2 neither parallel nor perpendicular
Step-by-step explanation:
* Lets revise how to find a slope of a line
- If a line passes through points (x1 , y1) and (x2 , y2), then the slope
of the line is [tex]m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]
- Parallel lines have same slopes
- Perpendicular lines have additive, multiplicative slopes
( the product of their slopes is -1)
* Lets solve the problem
∵ L1 passes through the point (1 , 10) and (-1 , 7)
- Let (1 , 10) is (x1 , y1) and (-1 , 7) is (x2 , y2)
∴ x1 = 1 , x2 = -1 and y1 = 10 , y2 = 7
∴ The slope of L1 is [tex]m1 = \frac{7-10}{-1-1}=\frac{-3}{-2}=\frac{3}{2}[/tex]
∵ L2 passes through the point (0 , 3) and (1 , 5)
- Let (0 , 3) is (x1 , y1) and (1 , 5) is (x2 , y2)
∴ x1 = 0 , x2 = 1 and y1 = 3 , y2 = 5
∴ The slope of L2 is [tex]m2=\frac{5-3}{1-0}=\frac{2}{1}=2[/tex]
∵ m1 = 3/2 and m2 = 2
- The two lines have different slopes and their product not equal -1
∴ The lines L1 and L2 neither parallel nor perpendicular
By calculating the slopes of L1 and L2, we find that they are 1.5 and 2 respectively. Since they are neither the same nor negative reciprocals, L1 and L2 are neither parallel nor perpendicular.
To determine if lines L1 and L2 are parallel, perpendicular, or neither, we need to calculate the slopes of both lines using the slope formula:
Slope formula: (y2 - y1) / (x2 - x1)
Calculating the slope of L1:
Points on L1: (1, 10) and (-1, 7)
Slope of L1 = (7 - 10) / (-1 - 1) = (-3) / (-2) = 1.5
Calculating the slope of L2:
Points on L2: (0, 3) and (1, 5)
Slope of L2 = (5 - 3) / (1 - 0) = 2 / 1 = 2
Since the slopes of L1 (1.5) and L2 (2) are neither the same nor negative reciprocals of each other, the lines L1 and L2 are neither parallel nor perpendicular.
Imagine a regression line that relates y = average systolic blood pressure to x = age. The average blood pressure for people 40 years old is 110, while for those 50 years old the average is 130. (a) What is the slope of the regression line? (Round the answer to one decimal place.)
Answer:
2.0
Step-by-step explanation:
x = age
y = average systolic blood pressure
x₁ = 40 years old, y₁ = 110 systolic blood pressure
x₂ = 50 years old, y₂ = 130 systolic blood pressure
[tex]\text{Slope of a line}=m=\frac{y_2-y_1}{x_2-x_1}\\\Rightarrow m= \frac{130-110}{50-40}\\\Rightarrow\frac{20}{10}\\\Rightarrow m= 2.0[/tex]
∴ Slope of the regression line is 2.0
Final answer:
The slope of the regression line relating average systolic blood pressure to age is 2.0 when rounded to one decimal place.
Explanation:
To find the slope of the regression line relating average systolic blood pressure (y) to age (x), we can use the two points provided (x1, y1) = (40, 110) and (x2, y2) = (50, 130). The slope (m) of a line passing through two points is calculated using the formula:
m = (y2 - y1) / (x2 - x1)
Substituting the given values:
m = (130 - 110) / (50 - 40) = 20 / 10 = 2
Therefore, the slope of the regression line is 2.0 when rounded to one decimal place.
Using the Extended Euclidean Algorithm, find integers x and y such that 26x + 9y = 1.
Answer:
The solution is: x=-1 and y=3.
Step-by-step explanation:
Let's find the solution, but first let's remember the following:
A / B = C + R where:
A=dividend, B=divisor, C=quotient, and R=remainder. This can be express as follows:
A = (C * B) + R, which is the structure we are going to use next.
Using the Euclidian Algorithm we need to find the highst common factor (HCF) between the coefficients from your equation, this means:
The original equation: 26x+9y=1 is in the form Ax+By=C, so A=26, B=9 and C=1.
We need to find the HCF of 'A' and 'B'. Using the Euclidan Algorithm (EA), so we have:
A = (C * B) + R, using our values:
26 = (2 * 9) + 8, look that the divisor (B) is 9 and the remainder (R) is 8.
Now using the (EA) we divide the divisor (B=9) by the obtained remainder (R=8). And we do the same for each obtained result until the las remainder (R) is equal to 0, like this:
A = (C * B) + R
9 = (8 * 1) + 1
using the divisor (B=8) and the remainder (R=1) we obtain:
A = (C * B) + R
8 = (1 * 8) + 0, look that the remainder is now 0, so in summary we can use the method as follows:
26 = (2 * 9) + 8
9 = (8 * 1) + 1
8 = (1 * 8) + 0; and this equations are the ones we are going to use in order to find a solution.
Next step is to use the equation before R=0, so:
9 = (8 * 1) + 1, which is:
9 - (8 * 1) = 1; but if you consider the first obtained equation: 26 = (2 * 9) + 8, we can write:
26 - (2 * 9) = 8, and we can use this expression in the previous one, so:
9 - (8 * 1) = 1, is:
9 - ((26 - (2 * 9)) * 1) = 1, simplifying:
9 - 26 + (2*9) = 1
9 - 26 + (9 + 9) = 1
-26 + (9 + 9 + 9) = 1
-26 + (3 * 9) = 1
26*(-1) + 9*(3) = 1; if you compare the last expression with the original equation, which is: 26x+9y=1, you can see the similarity, where x=-1 and y=3.
So, the solution is: x=-1 and y=3.