I suppose you're supposed to prove that set intersection is distributive across a union,
[tex]A\cap(B\cup C)=(A\cap B)\cup(A\cap C)[/tex]
Two sets are equal if they are subsets of one another. To prove a set [tex]X[/tex] is a subset of another set [tex]Y[/tex], you have to show that any element [tex]x\in X[/tex] also belongs to [tex]Y[/tex].
Let [tex]x\in A\cap(B\cup C)[/tex]. By definition of intersection, both [tex]x\in A[/tex] and [tex]x\in B\cup C[/tex]. By definition of union, either [tex]x\in B[/tex] or [tex]x\in C[/tex]. If [tex]x\in B[/tex], then clearly [tex]x\in A\cap B[/tex]; if [tex]x\in C[/tex], then [tex]x\in A\cap C[/tex]. Either way, [tex]x\in(A\cap B)\cup(A\cap C)[/tex]. Hence [tex]A\cap(B\cup C)\subseteq(A\cap B)\cup(B\cap C)[/tex].
The proof in the other direction uses the same sort of reasoning. Let [tex]x\in(A\cap B)\cup(A\cap C)[/tex]. Then either [tex]x\in A\cap B[/tex] or [tex]x\in A\cap C[/tex]. If [tex]x\in A\cap B[/tex], then both [tex]x\in A[/tex] and [tex]x\in B[/tex]; if [tex]x\in A\cap C[/tex], then both [tex]x\in A[/tex] and [tex]x\in C[/tex]. So certainly [tex]x\in A[/tex], and either [tex]x\in B[/tex] or [tex]x\in C[/tex] so that [tex]x\in B\cup C[/tex]. Hence [tex](A\cap B)\cup(A\cap C)\subseteq A\cap(B\cup C)[/tex].
Both sets are subsets of one another, so they are equal.
Which equation represents the magnitude of an
earthquake that is 100 times more intense than a
standard earthquake?
Answer:
m=log 100s/S
Step-by-step explanation:
howdy!
answer is in the attachment below :)
The quotient of a number increased by 13 and -7 is -4
The number in question is found by setting up the equation (x + 13) / -7 = -4, and solving for 'x'. Following order of operations and sign rules, we determine that the number is 15.
Explanation:The question asks us to find a number when given that the quotient of that number increased by 13 and -7 is -4. To solve this, we set up an equation and follow the multiplication and division rules for signs and the order of operations.
Let the unknown number be 'x'. According to the problem, (x + 13) / -7 = -4. Multiplying both sides by -7 to eliminate the denominator, we get x + 13 = (-7)(-4). Applying the rule that the product of two negative numbers is positive, we simplify the right side to get x + 13 = 28. Now, we subtract 13 from both sides to isolate 'x': x = 28 - 13, which gives us x = 15.
The number in question is therefore 15.
A student has a monthly budget of $800. She can spend her budget on two items, X and Y. Each unit of X costs $20 and each unit of Y costs $10. If the student has a utility function of U = 348X + 100Y + 6X2 + 4Y2 + 2XY, what is the optimal amount of X and Y for her to consume to have the maximum utility? What is this total utility? What is the value of lambda and what does this mean?
Answer:
Check the explanation
Step-by-step explanation:
Total utility is the overall satisfaction that a particular consumer received from consuming a given overall quantity of a good or service, To calculate the value of total utility economists utilize the following basic total utility formula: TU = U1 + MU2 + MU3
Kindly check the attached image below to see the step by step explanation to the question above.
Suppose parts (a) through (d) below provide results for a study on the role of calcium in reducing the symptoms of PMS. For each of the parts, compute an approximate 95% confidence interval for the difference in mean symptom scores between the placebo and calcium-treated conditions for the symptom listed. In each case, the results given are mean ± standard deviation. Suppose there were 228 participants in the placebo group and 212 in the calcium-treated group. (Round your answers to two decimal places.)
(a) mood swings: placebo = 0.70 ± 0.78; calcium = 0.50 ± 0.53
(b) crying spells: placebo = 0.39 + 0.57; calcium = 0.21 + 0.40
(c) aches and pains: placebo = 0.45 + 0.60; calcium = 0.37 + 0.45
(d) craving sweets or salts: placebo = 0.60 + 0.75; calcium = 0.44 + 0.61
Answer:
Step-by-step explanation:
Hello!
To test if calcium reduces the symptoms of PMS two independent groups of individuals are compared, the first group, control, is treated with the placebo, and the second group is treated with calcium.
The parameter to be estimated is the difference between the mean symptom scores of the placebo and calcium groups, symbolically: μ₁ - μ₂
There is no information about the distribution of both populations X₁~? and X₂~? but since both samples are big enough, n₁= 228 and n₂= 212, you can apply the central limit theorem and approximate the sampling distribution to normal X[bar]₁≈N(μ₁;δ₁²/n) and X[bar]₂≈N(μ₂;δ₂²/n)
The formula for the CI is:
[(X[bar]₁-X[bar]₂) ± [tex]Z_{1-\alpha /2}[/tex] * [tex]\sqrt{\frac{S^2_1}{n_1} +\frac{S^2_2}{n_2} }[/tex]]
95% confidence level [tex]Z_{1-\alpha /2}= Z_{0.975}= 1.96[/tex]
(a) mood swings: placebo = 0.70 ± 0.78; calcium = 0.50 ± 0.53
X₁: Mood swings score of a participant of the placebo group.
X₂: Mood swings score of a participant of the calcium group.
[(0.70-0.50) ± 1.96 * [tex]\sqrt{\frac{0.78^2}{228} +\frac{0.53^2}{212} }[/tex]]
[0.076; 0.324]
(b) crying spells: placebo = 0.39 + 0.57; calcium = 0.21 + 0.40
X₁: Crying spells score of a participant of the placebo group.
X₂: Crying spells score of a participant of the calcium group.
[(0.39-0.21) ± 1.96 * [tex]\sqrt{\frac{0.57^2}{228} +\frac{0.40^2}{212} }[/tex]]
[0.088; 0.272]
(c) aches and pains: placebo = 0.45 + 0.60; calcium = 0.37 + 0.45
X₁: Aches and pains score of a participant of the placebo group.
X₂: Aches and pains score of a participant of the calcium group.
[(0.45-0.37) ± 1.96 * [tex]\sqrt{\frac{0.60^2}{228} +\frac{0.45^2}{212} }[/tex]]
[-0.019; 0.179]
(d) craving sweets or salts: placebo = 0.60 + 0.75; calcium = 0.44 + 0.61
X₁: Craving for sweets or salts score of a participant of the placebo group.
X₂: Craving for sweets or salts score of a participant of the calcium group.
[(0.60-0.44) ± 1.96 * [tex]\sqrt{\frac{0.75^2}{228} +\frac{0.61^2}{212} }[/tex]]
[0.032; 0.287]
I hope this helps!
Using the z-distribution, the 95% confidence intervals are:
a) (0.08, 0.32).
b) (0.09, 0.27).
c) (-0.02, 0.18).
d) (0.03, 0.29).
We have to find the critical value, which is z with a p-value of [tex]\frac{1 + \alpha}{2}[/tex], in which [tex]\alpha[/tex] is the confidence level.
In this problem, [tex]\alpha = 0.95[/tex], thus, z with a p-value of [tex]\frac{1 + 0.95}{2} = 0.975[/tex], which means that it is z = 1.96.
Item a:
The standard errors are:
[tex]s_P = \frac{0.78}{\sqrt{228}} = 0.0517[/tex]
[tex]s_C = \frac{0.53}{\sqrt{212}} = 0.0364[/tex]
For the distribution of the differences, we have that:
[tex]\overline{x} = \mu_P - \mu_C = 0.7 - 0.5 = 0.2[/tex]
[tex]s = \sqrt{s_P^2 + s_C^2} = \sqrt{0.0517^2 + 0.0364^2} = 0.0632[/tex]
The interval is:
[tex]\overline{x} \pm zs[/tex]
Hence:
[tex]\overline{x} - zs = 0.2 - 1.96(0.0632) = 0.08[/tex]
[tex]\overline{x} + zs = 0.2 + 1.96(0.0632) = 0.32[/tex]
The interval is (0.08, 0.32).
Item b:
The standard errors are:
[tex]s_P = \frac{0.57}{\sqrt{228}} = 0.03775[/tex]
[tex]s_C = \frac{0.4}{\sqrt{212}} = 0.02747[/tex]
For the distribution of the differences, we have that:
[tex]\overline{x} = \mu_P - \mu_C = 0.39 - 0.21 = 0.18[/tex]
[tex]s = \sqrt{s_P^2 + s_C^2} = \sqrt{0.03775^2 + 0.02747^2} = 0.0467[/tex]
Hence:
[tex]\overline{x} - zs = 0.18 - 1.96(0.0467) = 0.09[/tex]
[tex]\overline{x} + zs = 0.18 + 1.96(0.0467) = 0.27[/tex]
The interval is (0.09, 0.27).
Item c:
The standard errors are:
[tex]s_P = \frac{0.6}{\sqrt{228}} = 0.0397[/tex]
[tex]s_C = \frac{0.45}{\sqrt{212}} = 0.0309[/tex]
For the distribution of the differences, we have that:
[tex]\overline{x} = \mu_P - \mu_C = 0.45 - 0.37 = 0.08[/tex]
[tex]s = \sqrt{s_P^2 + s_C^2} = \sqrt{0.0397^2 + 0.0309^2} = 0.0503[/tex]
Hence:
[tex]\overline{x} - zs = 0.08 - 1.96(0.0503) = -0.02[/tex]
[tex]\overline{x} + zs = 0.08 + 1.96(0.0503) = 0.18[/tex]
The interval is (-0.02, 0.18).
Item d:
The standard errors are:
[tex]s_P = \frac{0.75}{\sqrt{228}} = 0.0497[/tex]
[tex]s_C = \frac{0.61}{\sqrt{212}} = 0.0419[/tex]
For the distribution of the differences, we have that:
[tex]\overline{x} = \mu_P - \mu_C = 0.60 - 0.44 = 0.16[/tex]
[tex]s = \sqrt{s_P^2 + s_C^2} = \sqrt{0.0497^2 + 0.0419^2} = 0.065[/tex]
Hence:
[tex]\overline{x} - zs = 0.16 - 1.96(0.065) = 0.03[/tex]
[tex]\overline{x} + zs = 0.16 + 1.96(0.065) = 0.29[/tex]
The interval is (0.03, 0.29).
A similar problem is given at https://brainly.com/question/15297663
How do i know if 4/6 < 3/10?
Answer:
4/6 > 3/10
Step-by-step explanation:
4/6 < 3/10
First get a common denominator of 30
4/6 *5/5 < 3/10 *3/3
20/30 < 9/30
This is false since 20 > 9
Which of the following are true about regression with one predictor variable (often called "simple regression")? Check all that apply.
A. The slope describes the amount of change in Y for a one-unit increase in X
B. The regression equation is the line that best fits a set of data as determined by having the least squared error
C. The slope, b, of the regression equation has the same value as r, the estimated correlation
Answer:
A. The slope describes the amount of change in Y for a one-unit increase in X .B. The regression equation is the line that best fits a set of data as determined by having the least squared error.Step-by-step explanation:
In statistics, linear regression is a analysis we do to describe the relationship between two variables. With this study, we pretend to know if there's a positive or negative correlation between those variables, if that correlation is strong or weak.
In a linear regression analysis, we modeled the data set using a regression equation, which is basically the line that best fits to the data set, this line is like the average where the majority of data falls. That means choice A is right.
When we use linear equations, we need to know its characteristics, and the most important one is the slope, which is the ratio between the dependent variable and the independent variable. Basically, the slope states the unit rate between Y and X, in other words, it states the amount of Y per unit of X. That means choice B is correct.
Therefore, the correct answers are A and B.
The options that are true about regression with one predictor variable include:
A. The slope describes the amount of change in Y for a one-unit increase in XB. The regression equation is the line that best fits a set of data as determined by having the least squared error.Regression simply refers to a statistical measurement which attempts to determine the strength that exists between a dependent variable and the independent variables.
It should be noted that in one predictor variable, the slope describes the amount of change in Y for a one-unit increase in X and the regression equation is the line that best fits a set of data as determined by having the least squared error.
Read related link on:
https://brainly.com/question/11503532
Which point has coordinates of (2, 0)?
Answer:
J
Step-by-step explanation:
Suppose that E and F are two events and that Upper P (Upper E and Upper F )equals0.3 and Upper P (Upper E )equals0.5. What is Upper P (F|E )? Upper P (F|E )equals nothing (Type an integer or a decimal.)
Answer:
[tex]P(\frac{F}{E}) =\frac{0.3}{0.5} =0.6[/tex]
Step-by-step explanation:
Step 1:-
Suppose that E and F are two events and that P(E n F) = 0.3
also given P(E) =0.5
Conditional probability:-
if E₁ and E₂ are two events in a Sample S and P(E₁)≠ 0, then the probability of E₂ , after the event E₁ has occurred, is called the Conditional probability
of the event E₂ given E₁ and is denoted by
[tex]P(\frac{F}{E}) = \frac{P(EnF)}{P(E)}[/tex]
[tex]P(\frac{F}{E}) =\frac{0.3}{0.5} =0.6[/tex]
solve -6 4/9-3 2/9-82/9
Answer: The final answer in proper fraction is 169/9
Step-by-step explanation:
Given the expression
-6 4/9-3 2/9-82/9
Firstly let us convert all mixed fraction to proper fraction to further simplify the expression
-58/9 - 29/9 - 82/9
We now have all terms in proper fraction, we can continue by finding the LCM which is 9
= (- 58-29-82)/9
= 169/9
A package contains 4 red, 2 green, 8 purple, and 6 blue jelly beans. What is the probability of choosing a purple jelly bean, eating it, and then choosing a blue jelly bean?
The probability of choosing a purple jelly bean, eating it, and then choosing a blue jelly bean is 12/95.
The probability of choosing a purple jelly bean, eating it, and then choosing a blue jelly bean is the product of the probability of choosing a purple jelly bean and the probability of choosing a blue jelly bean given that a purple jelly bean was already chosen.
The probability of choosing a purple jelly bean is 8/20 = 2/5.
The probability of choosing a blue jelly bean given that a purple jelly bean was already chosen is 6/19. This is because there are only 6 blue jelly beans left after the purple jelly bean is eaten, and there are a total of 19 jelly beans left.
Therefore, the probability of choosing a purple jelly bean, eating it, and then choosing a blue jelly bean is 2/5 * 6/19 = 12/95.
Another way to solve this problem is to use the following formula:
P(A and B) = P(A) * P(B | A)
Where:
P(A) is the probability of event A happening
P(B | A) is the probability of event B happening given that event A already happened
In this case, event A is choosing a purple jelly bean and event B is choosing a blue jelly bean.
Therefore, the probability of choosing a purple jelly bean, eating it, and then choosing a blue jelly bean is:
P(purple jelly bean) * P(blue jelly bean | purple jelly bean) = 2/5 * 6/19
= 12/95.
To learn more about probability here:
https://brainly.com/question/32117953
#SPJ12
8/12 - 2/12 =
THIS IS WORTH 100pts the only question pleaseeeeee
Answer:
1/2
Step-by-step explanation:
Since they have the same denominator, you can just subtract the numerators. So, 8-2=6.
6/12 can be simplified to 1/2.
Answer:
the answer is 1/2 or 0.5
Step-by-step explanation:
hope this helps!
Solve: (1/8)^-3a=512
Answer:
a = 1
Step-by-step explanation:
The problem is written as a linear equation:
((1/8)^-3)a = 512
512a = 512 . . . . simplify
a = 1 . . . . . . . . . divide by the coefficient of a
___
We suspect you might intend the exponential equation:
(1/8)^(-3a) = 512
512^a = 512 . . . . . simplify
a = 1 . . . . . . . . . . . compare bases and exponents
equivalently, take the log to the base 512:
a·1 = 1
a = 1
solve x+3<9
[tex]x + 3 < 9[/tex]
X + 3 < 9
Subtract 3 from both sides:
X < 6
The answer is x < 6
Select a composite number to break into factors. Continue
factoring until all factors are prime.
Final answer:
To factor a composite number into primes, divide it by its smallest divisor that is not 1, then continue dividing the quotient until all factors are prime. An example is the number 60, which factors into 2 x 2 x 3 x 5, or 2² x 3 x 5 when using exponents for the repeated factor of 2.
Explanation:
The subject of the question is to select a composite number and break down its factors until all the factors are prime. As an example, let's choose the composite number 60. Here's how you can factor it into primes:
First, note that 60 is an even number, so it is divisible by 2. Start by dividing 60 by 2 to get 30.
Now, 30 is still even, so we can divide by 2 again to get 15.
15 is divisible by 3, so when we divide it by 3, we get 5, which is a prime number.
So, the prime factorization of 60 is 2 x 2 x 3 x 5, often written using exponents for any repeated factors as 22 x 3 x 5.
Through factorization, we have converted the composite number into a product of prime factors. Each factor multiplication is a step that requires one to find two numbers that multiply to the number we are factoring and continuing this process until we reach numbers that are prime.
A shop has the following offers. Fig rolls (125g packet) Normal price £1.08. Buy one, get 2nd half price.
The total cost of two packets of fig rolls, with the second one at half price, is £1.62. The calculation involves the normal price of one packet plus half of that price for the second one.
Explanation:The question involves calculating the total cost of fig rolls when a shop offers a deal where if you buy one packet, you get the second packet at half the price.
To find the total cost of two packets under this offer, we first take the normal price of one packet (£1.08) and add it to half of that price (which is £1.08 / 2 = £0.54). The total cost for two packets is therefore £1.08 (first packet) + £0.54 (second packet at half price), which equals £1.62.
For 3 packets of fig rolls and 6 packets of crisps, the total price is £8.42 considering the offers of buy one, get 2nd half price and three for the price of two, respectively.
For the fig rolls:
Normal price for 1 packet = £1.08
Buy one, get 2nd half price.
So, for 3 packets of fig rolls, we'd pay for 2 and get the third at half price.
Total cost for 3 packets of fig rolls = Cost of 2 packets + Half price of 1 packet
[tex]= 2 \times £1.08 + \frac{1}{2} \times £1.08[/tex]
= £2.16 + £0.54
= £2.70
For the crisps:
Normal price for 1 packet = £1.43
Three for the price of two.
So, for 6 packets of crisps, we'd pay for 4 and get 2 free.
Total cost for 6 packets of crisps = Cost of 4 packets
[tex]\(= 4 \times £ 1.43\)[/tex]
= £5.72
Therefore, the total price for 3 packets of fig rolls and 6 packets of crisps would be:
Total = Cost of 3 fig roll packets + Cost of 6 crisps packets
= £2.70 + £5.72
= £8.42
Complete Question:
Simplify.
(4x’y - 9xy + 4) + (-7r’y+ 4xy? + 8)
Answer:
4 y x ' − 9 x y − 7 y r ' + 4 x y? + 12
Step-by-step explanation:
Simplified the expression.
<3
Answer:
4 y x ' − 9 x y − 7 y r ' + 4 x y ? + 12
What is the first step in solving 2x=y X+y=30
Answer: x = 10 y=20
Step-by-step explanation:
You can answer this question by plugging in each equation:
2x=y, x+y=30. Let us plug y as 2x in the second equation x+y=30
x+2x= 30
3x= 30
x=10
After we found x we can then find y by plugging the 10 for x.
2(10) = y
y =20
or you could plug in the other equation
10+y=30
subtract 10 from 30 and we get 20
to double check we can plug in both numbers
2(10) = 20 which is correct
and 10 + 20 = 30 which is correct
In order for a constitutional amendment to the Florida constitution to pass 60% of the popular vote must support the amendment. A researcher is interested in determining if the more than sixty percent of the voters would support a new amendment about higher education. The researcher asks 500 random selected potential voters if they would support the amendment. Define the parameter.
Answer:
p=population of Floridians that would support the amendment
Step-by-step explanation:
we are given parameters are,
n = Sample size = 500
and p = Population proportion = 60% = 0.6
p = the population proportion of Floridians that would the amendment.
Answer:
A
Step-by-step explanation:
The complete question is:
In order for a constitutional amendment to the Florida constitution to pass 60% of the popular vote must support the amendment. A researcher is interested in determining if the more than sixty percent of the voters would support a new amendment about higher education. The researcher asks 500 random selected potential voters if they would support the amendment. Define the parameter.
A) phat= sample proportion of 500 Floridans that would support the ammendment
B) p= population proportion of Floridans that would support the ammendment
C) phat= population proportion of Floridans that would support the ammendment
D) p= sample proportion of 500 Floridans that would support the ammendment
p is the actual probability of an event which is 0.6
phat is the value calculated from the sample observation
here a sample of 500 Floridans is taken and probability from sample is being observed. So phat is the parameter which is the population proportion of 500 Floridans that would support the ammendment
A sociologist develops a test to measure attitudes about public transportation, and 27 randomly selected subjects are given the test. Their mean score is 76.2 and their standard deviation is 21.4. Construct the 90% confidence interval for the mean score of all such subjects.Immersive Reader
Answer:
The 90% confidence interval for the mean score of all such subjects is between 39.7 and 112.7
Step-by-step explanation:
We have the standard deviation of the sample, so we use the t-distribution to build the confidence interval.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 27 - 1 = 26
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 26 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.9}{2} = 0.95([tex]t_{95}[/tex]). So we have T = 1.7056
The margin of error is:
M = T*s = 1.7056*21.4 = 36.50.
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 76.2 - 36.5 = 39.7
The upper end of the interval is the sample mean added to M. So it is 76.2 + 36.5 = 112.7
The 90% confidence interval for the mean score of all such subjects is between 39.7 and 112.7
Given the following information about a hypothesis test of the difference between two means based on independent random samples, which one of the following is the correct rejection region at a significance level of .05? Assume that the samples are obtained from normally distributed populations having equal variances.HA: μA > μB, = 12, = 9, s1 = 5, s2 = 3, n1 = 13, n2 = 10.A. Reject H0 if Z > 1.96B. Reject H0 if Z > 1.645C. Reject H0 if t > 2.08D. Reject H0 if t > 1.782E. Reject H0 if t > 1.721
Answer:
Null hypothesis:[tex]\mu_{A} \leq \mu_{B}[/tex]
Alternative hypothesis:[tex]\mu_{A} > \mu_{B}[/tex]
Since we dpn't know the population deviations for each group, for this case is better apply a t test to compare means, and the statistic is given by:
[tex]t=\frac{\bar X_{A}-\bar X_{B}}{\sqrt{\frac{\sigma^2_{A}}{n_{A}}+\frac{\sigma^2_{B}}{n_{B}}}}[/tex] (1)
Now we need to find the degrees of freedom given by:
[tex] df = n_A + n_B -2= 13+10-2=21[/tex]
And now since we are conducting a right tailed test we are looking ofr a value who accumulates 0.05 of the are on the right tail fo the t distribution with df =21 and we got:
[tex] t_{cric}= 1.721[/tex]
And for this case the rejection zone would be:
E. Reject H0 if t > 1.721
Step-by-step explanation:
Data given and notation
[tex]\bar X_{A}=12[/tex] represent the mean for 1
[tex]\bar X_{B}=9[/tex] represent the mean for 2
[tex]s_{A}=5[/tex] represent the sample standard deviation for 1
[tex]s_{2}=3[/tex] represent the sample standard deviation for 2
[tex]n_{1}=13[/tex] sample size for the group 1
[tex]n_{2}=10[/tex] sample size for the group 2
t would represent the statistic (variable of interest)
[tex]\alpha=0.05[/tex] significance level provided
Develop the null and alternative hypotheses for this study
We need to conduct a hypothesis in order to check if the mean for group A is higher than the mean for B:
Null hypothesis:[tex]\mu_{A} \leq \mu_{B}[/tex]
Alternative hypothesis:[tex]\mu_{A} > \mu_{B}[/tex]
Since we dpn't know the population deviations for each group, for this case is better apply a t test to compare means, and the statistic is given by:
[tex]t=\frac{\bar X_{A}-\bar X_{B}}{\sqrt{\frac{\sigma^2_{A}}{n_{A}}+\frac{\sigma^2_{B}}{n_{B}}}}[/tex] (1)
Now we need to find the degrees of freedom given by:
[tex] df = n_A + n_B -2= 13+10-2=21[/tex]
And now since we are conducting a right tailed test we are looking ofr a value who accumulates 0.05 of the are on the right tail fo the t distribution with df =21 and we got:
[tex] t_{cric}= 1.721[/tex]
And for this case the rejection zone would be:
E. Reject H0 if t > 1.721
A survey was conducted to measure the height of men. In the survey, respondents were grouped by age. In the 20-29 age group, the heights were normally distributed, with a mean of 69.9 inches and a standard deviation of 3.0 inches. a study participant is randomly sleected. what height cuts off the top 5%
Answer:
The height that cuts off the top 5% is 74.83 inches.
Step-by-step explanation:
We are given that in the survey, respondents were grouped by age. In the 20-29 age group, the heights were normally distributed, with a mean of 69.9 inches and a standard deviation of 3.0 inches.
Let X = heights of respondents
So, X ~ N([tex]\mu=69.9,\sigma^{2} =3^{2}[/tex])
The z-score probability distribution for normal distribution is given by;
Z = [tex]\frac{ X -\mu}{\sigma}[/tex] ~ N(0,1)
where, [tex]\mu[/tex] = mean height = 69.9 inches
[tex]\sigma[/tex] = standard deviation = 3.0 inches
The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.
Now, we have to find the height that cuts off the top 5%, that means;
P(X > [tex]x[/tex]) = 0.05 {where [tex]x[/tex] is the height that cuts off top 5%}
P( [tex]\frac{ X -\mu}{\sigma}[/tex] > [tex]\frac{ x -69.9}{3}[/tex] ) = 0.05
P(Z > [tex]\frac{ x -69.9}{3}[/tex] ) = 0.05
Now, in the z table the critical value of X that gives the area of top 5% is given as 1.6449.
So, [tex]\frac{ x -69.9}{3} = 1.6449[/tex]
[tex]x -69.9= 1.6449 \times 3[/tex]
[tex]x[/tex] = 69.9 + 4.9347 = 74.83
Hence, the height that cuts off the top 5% is 74.83 inches.
Samuel bought 32 and 1/2 ft of window trim at a hardware store the trim cost $1.75 per foot including sales tax if Samuel paid with a $100 bill how much change should he have received
Answer:
The amount of change he should received is
$100 - $56.875
= $43.125
= $43.13
Step-by-step explanation:
Length of window trim = 32 and 1/2 ft
Cost per foot = $1.75
Amount paid = $100
Total cost of window trim = 32.5×1.75 = $56.875
The amount of change he should received is
$100 - $56.875
= $43.125
= $43.13
As Saturn revolves around the sun, it travels at a speed of approximately 6 miles per second. Convert this speed to miles per minute. At this speed, how many miles will Saturn travel in 3 minutes?
Answer:360 miles per minute , and 1080 in 3 minutes
Step-by-step explanation:
of the 85 points scored by the hpa thunderbirds , jayla scored 20%. how many points did jayla score?
Answer:
17 points
Step-by-step explanation:
20% × 85 = 0.20 × 85 = 17
Jayla scored 17 points.
a snack mix recipe calls for 1 1/4 cups of dip and 1/2 cups of veggies. Parkers want to make the same recipe using 1 cup of veggies. How many cups of dip will parker need?
Answer:
2 1/2 cups
Step-by-step explanation:
You are doubling your recipe. You would do 1 1/4 × 2. First, 1 × 2 = 2 and then 1/4 × 2 = 1/2. Put them together for your answer. I hope this helped.
Final answer:
Parker will need 2 1/2 cups of dip.
Explanation:
To find out how many cups of dip Parker will need, we can set up a proportion using the given information.
The snack mix recipe calls for 1 1/4 cups of dip and 1/2 cups of veggies.
Let's call the number of cups of dip Parker needs x.
The proportion will be: 1 1/4 cups / 1/2 cups = x cups / 1 cup.
To solve for x, we can cross multiply and then divide: (1 1/4) * 1 = (1/2) * x.
Simplifying both sides gives us 5/4 = 1/2 * x.
To isolate x, we can multiply both sides by the reciprocal of 1/2, which is 2/1: (5/4) * (2/1) = x.
Multiplying gives us x = 10/4, which simplifies to x = 2 1/2 cups.
represent the times necessary to perform three successive repair tasks at a service facility. Suppose they are normal random variables with means of 50 minutes, 60 minutes, and 40 minutes, respectively. The standard deviations are 15 minutes, 20 minutes, and 10 minutes, respectively
Question: The question is incomplete. What need to be calculated is not included in the question. Below is the question requirement and the answer.
a) Suppose X1, X2, and X3 are independent. All three repairs must be completed on a given object. What is the mean and variance of the total repair time for this object?
Answer:
Mean = 50 minutes
Variance = 725 minutes
Step-by-step explanation:
X₁ = 50
X₂ = 60
X₃ = 40
σ₁ = 15
σ₂ = 20
σ₃ = 10
Calculating the mean E(Y) using the formula;
E(Y) = E(X₁ +X₂ +X₃)/3
= (EX₁ + EX₂ + EX₃)/3
= (50 + 60 + 40)/3
= 50 minutes
Therefore, the mean of the total repair time for this object is 50 minutes
Calculating the variance V(Y) using the formula;
V(Y) = V(X₁ +X₂ +X₃)
= E(X₁) +E(X₂) + E(X₃)
= σ₁² + σ₂² + σ₃²
= 15² + 20² + 10²
= 225 + 400 + 100
= 725 minutes
Therefore, the variance of the total repair time for this object is 725 minutes
Uta invests an amount into a compound interest investment account that pays 6% a year. After six years she withdraws her total balance of $500. Using the formula A=p(1+r)t how much money did Uta initially invest?
Uta initially invest $353, if she withdraws $500 after six years with compound interest of 6% a year.
Step-by-step explanation:
The given is,
After six years she withdraws her total balance of $500
Interest rate 6 % a year ( compounded )
Step:1
Formula to calculate the future amount with an compound interest rate,
[tex]F=P(1+r)^{t}[/tex].............................(1)
Where, F - Future worth amount
P - Initial investment
r - Rate of interest
t - No. of years
Step:2
From the given,
F = $500
r = 6%
t = 6 years
Equation (1) becomes,
[tex]500 = P(1+0.06)^{6}[/tex]
= [tex]P(1.06)^{6}[/tex]
= P (1.41852)
[tex]P= \frac{500}{1.41852}[/tex]
= 352.48
≅ 353
P = $353
Result:
Uta initially invest $353, if she withdraws $500 after six years with compound interest of 6% a year.
Answer:
C- $352.48
Step-by-step explanation:
Just took test :]
PLEASE HELP ASAP!! Major question points!! geometry
Answer:
A
Step-by-step explanation:
If you plug in the numbers to the formula, A is the correct answer.
What is the constant proportionality
Answer:
The relationship between price and the number of empanadas is PROPORTIONAL.
1 Empanada = 50 cent = $0.5
Constant of PROPORTIONALITY = ½
Step-by-step explanation:
From the given table:
2 Empanadas = $1
6 Empanadas = $3
We see that, as the number of Empanadas increases, the amount in Dollars also increases. Such that:
Let E = Empanadas
$ = dollar
~ = sign of PROPORTIONALITY.
Therefore:
$ ~ E
$ = KE
Where K = constant of proportionality.
When E = 4; $ = 2
$2 = K4
K= 2/4
K = ½
$ = ½E (Binding formula)
This applies for all the number of Empanadas bought.
Answer:
.50
Step-by-step explanation:
I ready
Solve the equation using the distributive property and properties of equality.
-5(a + 3) = -55
What is the value of a?
O a
Ob
-14
-8
d
14
Answer:
a =8
Step-by-step explanation:
-5(a + 3) = -55
Distribute
-5a -15 = -55
Add 15 to each side
-5a-15+15 = -55+15
-5a = -40
Divide each side by -5
-5a/-5 = -40/-5
a = 8