Answer:
the particular solution is
Y_{p}= C +D\sin 5t +E\cos 5t + F\exp 4t + G\exp -2t
the differential operator that annihilate the non homogeneous differential equation is
D(D^2+5)
Step-by-step explanation:
hello,
i believe the non homogeneous differential equation is
[tex]U^{''} - 2U^{'} - 8= \cos 5x + 7[/tex]
the homogeneous differential equation of the above is
[tex]u^{''} -2u^{'} -8 =0[/tex]
the differential form of the above equation is
[tex]D^2-2D-8=0[/tex]
[tex](D-4)(D+2)=0[/tex]
thus the roots are 4 and -2.
thus the solution of the homogenous differential equation is given as
[tex]Y_{h} (t)= A\exp{4t} + B\exp{-2t}[/tex]
the differential operator of the non homogeneous equation is given as
[tex](D-4)(D+2)(u)=\cos 5x +7[/tex]
the differential operator [tex]D^2 +5[/tex] annihilates [tex]\cos 5x[/tex] and the differential operator D annihilates 7
applying [tex]D(D^2+5)[/tex] to both sides of the differential equation we have;
(D-4)(D+2)(u)=\cos 5x +7
[tex]D(D^2+5)(D-4)(D+2)=D(D^2+5)(\cos5x+7)[/tex][tex]D(D^2+5)(D-4)(D+2)=0[/tex]
the roots of the characteristic polynomial of the diffrential equation above are [tex]0, \cmplx 5i, -\cmplx 5i, 4, -2[/tex]
thus the particular solution is
[tex]Y_{p}= C\exp{0}+D\sin 5t +E\cos 5t + F\exp {4t} + G\exp {-2t}[/tex]
this gives us the particular solution
[tex]Y_{p}= C +D\sin 5t +E\cos 5t + F\exp 4t + G\exp -2t[/tex]
To use the annihilator method for the differential equation [tex]\(u'' - 2u' - 8 = \cos(5x) + 7\),[/tex] the operator [tex]\(D^3 + 25D\)[/tex] will annihilate the nonhomogeneous part [tex]\(\cos(5x) + 7\).[/tex] This operator reduces the nonhomogeneous function to zero. The differential operator combines the annihilation of both the cosine and constant terms.
To determine the form of a particular solution for the given differential equation[tex]\(u'' - 2u' - 8 = \cos(5x) + 7\),[/tex] we first identify a differential operator that annihilates the nonhomogeneous part [tex]\(\cos(5x) + 7\).[/tex]
For [tex]\(\cos(5x)\)[/tex] , the appropriate annihilator is [tex]\(D^2 + 25\)[/tex], where [tex]\(D\)[/tex] represents differentiation with respect to [tex]\(x\)[/tex].
This is because applying [tex]\(D^2 + 25\)[/tex] to [tex]\(\cos(5x)\)[/tex] will yield zero:
[tex]\(\frac{d^2}{dx^2}(\cos(5x)) + 25 \cos(5x) = -25\cos(5x) + 25\cos(5x) = 0 \).[/tex]For the constant term 7, the annihilator is simply [tex]\(D\)[/tex], since the derivative of a constant is zero:
[tex]\(\frac{d}{dx}(7) = 0.\)[/tex]Combining these, the overall differential operator that will annihilate [tex]\(\cos(5x) + 7\)[/tex] is:
[tex]\( (D)(D^2 + 25) = D^3 + 25D.\)[/tex]The differential operator [tex]\( D^3 + 25D \)[/tex] will annihilate the nonhomogeneous part [tex]\( \cos(5x) + 7 \),[/tex] reducing it to zero.
Find a6: 1, 1/2, 1/6, 1/24, 1/120, a6, 1/5,040, ...
Answer:
Is the #6 in the row. Is this a riddle
Answer:
its 1/720 i just took it
Step-by-step explanation:
A tourist who speaks English but no other language visits a region of Germany. If 35% of the residents speak English, 15% speak German, and 3% speak both English and German, what is the probability that the tourist will be able to talk with a randomly encountered resident of the region, given that the resident speaks German
Answer:
20% robability that the tourist will be able to talk with a randomly encountered resident of the region, given that the resident speaks German
Step-by-step explanation:
We use the conditional probability formula to solve this question. It is
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
In which
P(B|A) is the probability of event B happening, given that A happened.
[tex]P(A \cap B)[/tex] is the probability of both A and B happening.
P(A) is the probability of A happening.
In this problem, we have that:
Event A: Speaking German
Event B: Speaking English
3% speak both English and German
This means that [tex]P(A \cap B) = 0.03[/tex]
15% speak German
This means that [tex]P(A) = 0.15[/tex]
So
[tex]P(B|A) = \frac{0.03}{0.15} = 0.2[/tex]
20% robability that the tourist will be able to talk with a randomly encountered resident of the region, given that the resident speaks German
The sum of number times 3 and 15
Answer:
3x+15
Step-by-step explanation:
When it says "the sum of a number three times", it means 3x, because the x stands for multiplication and the problem says the sum sum is between 3x and the number 15. So your equation is 3x+15. Hope this helps ;)
What is the difference of the means of the distributions? 15 30 45 60
Answer:
The difference is 15.
Step-by-step explanation:
30-15=15
45-30=15
60-45=15
Answer:
I agree the difference is 15.
Step-by-step explanation:
The distance between flaws on a long cable is exponentially distributed with mean 12 m.
a. Find the probability that the distance between two flaws is greater than 15m.
b. Find the probability that the distance between two flaws is between 8 and 20 m.
c. Find the median distance.
d. Find the standard deviation of the distances.
e. Find the 65th percentile of the distances.
The question asks for various measures of an exponentially distributed statistic, the distance between flaws on a cable. To find these, we use formulas specific to the exponential distribution; for example, the median is calculated as ln(2) * mean, and the standard deviation is equal to the mean, computed with the formula σ = √variance = √mean.
Explanation:The problem can be modeled using the exponential distribution in statistics. The exponential distribution is often used to model the time elapsed between events in a Poisson point process, or in our case, the distance between the flaws in the cable.
The probability that the distance between two flaws is greater than 15m can be calculated using the formula:https://brainly.com/question/37170119
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In this problem, we're calculating properties of an exponential distribution representing the distances between flaws in a cable. The probability that a given distance is more than 15m is 22.31%, and between 8m and 20m is 48.57%. The median distance is around 8.317m, the standard deviation is 12m, and the 65th percentile is about 14.791m.
Explanation:In this problem, the distance between flaws on a long cable is exponentially distributed with a mean of 12 m. That means the lambda (λ) parameter's rate of occurring flaws per meter is 1/mean, or approximately 0.0833.
For a given exponential distribution, the probability that a random variable X is greater than x is given by P(X > x) = e^(-λx). So, to find the probability that the distance between flaws is greater than 15 m, we substitute 15 for x to get P(X > 15) = e^(-0.0833 * 15) approximately equals 0.2231 or 22.31%. The probability that the distance between two flaws is between 8 and 20 m will be P(8 < X < 20) = P(X < 20) - P(X < 8) which equates to (1 - e^(-0.0833 * 20)) - (1 - e^(-0.0833 * 8)). This calculates to approximately 0.4857 or 48.57%. From the properties of the exponential distribution, the median distance can be calculated using the formula ln2/λ, so the median is approximately 8.317 m. The standard deviation of an exponential distribution is the reciprocal of λ, which is simply the mean (μ). So the standard deviation is also 12 m. The 65th percentile of an exponential distribution can be calculated using the formula: -ln(1 - p) / λ where p is the percentile in decimal form. So the 65th percentile is -ln(1 - 0.65) / 0.0833 ≈ 14.791 m. Learn more about Exponential Distribution here:https://brainly.com/question/33722848
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You are doing marketing research about yogurt consumption. Based on your previous research, you feel sure that the population standard deviation of the number of yogurts consumed per year is 6. In other words, σ is known and σ = 6. You take a sample of 50 consumers and the sample mean is 32 yogurts consumed per year. In other words, = 32. You want to develop a confidence interval for μ푥(the population mean) such that you are 90% confident that the true value of μ lies within the interval.1. What is the value of ?훼
Answer:
Step-by-step explanation:
Confidence interval is written in the form,
(Sample mean - margin of error, sample mean + margin of error)
The sample mean, x is the point estimate for the population mean.
Since the sample size is large and the population standard deviation is known, we would use the following formula and determine the z score from the normal distribution table.
Margin of error = z × σ/√n
Where
σ = population standard Deviation
n = number of samples
From the information given
1) x = 32
σ = 6
n = 50
To determine the z score, we subtract the confidence level from 100% to get α
α = 1 - 0.90 = 0.1
α/2 = 0.1/2 = 0.05
This is the area in each tail. Since we want the area in the middle, it becomes
1 - 0.05 = 0.95
The z score corresponding to the area on the z table is 1.645. Thus, confidence level of 90% is 1.645
Margin of error = 1.645 × 6/√50 = 1.4
Confidence interval = 32 ± 1.4
The lower end of the confidence interval is
32 - 1.4 = 30.6
The upper end of the confidence interval is
32 + 1.4 = 33.4
If ax + y=23, 3x - y = 9, and x =8, what is the value of a ?
Answer:
a = 1
Step-by-step explanation:
x = 8
3x - y = 9
3(8) - y = 9
24 - y = 9
-y = 9 - 24
-y = -15
y = 15
ax + y = 23
a(8) + 15 = 23
8a = 23 - 15
8a = 8
a = 8/8
a = 1
How many inches is 50cm?
Answer:
Step-by-step explanation:
Answer:
19.5 inches or 19.685 inches for length
Step-by-step explanation:
50•0.39. 50÷3
19.5. 19.685
how to convert centimeters to inches:
multiply the centimeter by 0.39. example 10•0.39= 3.9 inches.
If you want centimeters to inches as length, then divide the centimeters by 3. example: 10÷3= 3.3333333333 inches
The owner of Get-A-Away Travel has recently surveyed a random sample of 337 customers to determine whether the mean age of the agency's customers is over 20. The appropriate hypotheses are Upper H 0: muequals20, Upper H Subscript a Baseline : mu greater than 20. If he concludes the mean age is over 20 when it is not, he makes a __________ error. If he concludes the mean age is not over 20 when it is, he makes a __________ error.
Answer:
On this case we want to test if the mean age of the agency's customers is over 20, so the system of hypothesis would be:
Null hypothesis: [tex]\mu \leq 20[/tex]
Alternative hypothesis: [tex]\mu >20[/tex]
If he concludes the mean age is over 20 when it is not, he makes a type I error . If he concludes the mean age is not over 20 when it is, he makes a Type II error error.
Step-by-step explanation:
Previous concepts
A hypothesis is defined as "a speculation or theory based on insufficient evidence that lends itself to further testing and experimentation. With further testing, a hypothesis can usually be proven true or false".
The null hypothesis is defined as "a hypothesis that says there is no statistical significance between the two variables in the hypothesis. It is the hypothesis that the researcher is trying to disprove".
The alternative hypothesis is "just the inverse, or opposite, of the null hypothesis. It is the hypothesis that researcher is trying to prove".
Type I error, also known as a “false positive” is the error of rejecting a null hypothesis when it is actually true. Can be interpreted as the error of no reject an alternative hypothesis when the results can be attributed not to the reality.
Type II error, also known as a "false negative" is the error of not rejecting a null hypothesis when the alternative hypothesis is the true. Can be interpreted as the error of failing to accept an alternative hypothesis when we don't have enough statistical power.
Solution to the problem
On this case we want to test if the mean age of the agency's customers is over 20, so the system of hypothesis would be:
Null hypothesis: [tex]\mu \leq 20[/tex]
Alternative hypothesis: [tex]\mu >20[/tex]
If he concludes the mean age is over 20 when it is not, he makes a type I error . If he concludes the mean age is not over 20 when it is, he makes a Type II error error.
When the travel agency owner concludes the mean age is over 20 when it's not, it's called a Type I error. If he concludes it's not over 20 when it is, it is a Type II error.
The scenario described involves a hypothesis test concerning the mean age of customers at a travel agency. When the travel agency owner incorrectly concludes that the mean age is over 20 when in fact it is not, he is making a Type I error. Conversely, if he concludes that the mean age is not over 20 when it actually is, that would be a Type II error. Understanding the consequences of these errors is critical in statistics because they affect decision-making processes based on data analysis.
You and a friend are selling lemonade. You sell three times as many cups as your friend. What percent of the cups sold were sold by your friend? Explain.
Answer:
Step-by-step explanation:
Friend sells x cups
You sell 3x cups
Total cups sold:: 4x
Ans: x/4x = 1/4 = 25%
Final answer:
The fraction of cups sold by your friend is x/4x, which gives us 25% of the total sales when converted to a percentage.
Explanation:
To find out what percent of the cups sold were sold by your friend, we can set up a simple ratio.
Let's assume your friend sold x cups.
According to the problem, you sold three times as many cups, so you sold 3x cups.
The total number of cups sold is the sum of the cups you both sold, which is x + 3x = 4x cups.
Now, we want to find out what fraction of the total sales x represents.
Since your friend sold x cups out of the total 4x, the fraction is x/4x.
To convert this fraction to a percentage, we multiply it by 100%.
Therefore, the percentage of cups sold by your friend is (x/4x) × 100% = 25%.
This calculation shows that your friend sold 25% of the cups.
We want to estimate the actual difference between the proportions of non-smokers and smokers who said "yes" to federal tax increase. Notation: 1=non-smokers and 2=smokers. Based on this data, what is the upper bound for a 95% confidence interval for the difference in the population proportions
Answer:
Upper bond is 0.398
Step-by-step explanation:
See attached file
Yesterday, a flower stand sold a dozen bouquets of flowers, each of which sold for $10. Today, the stand made the same amount of money but the price of a bouquet was increased to $12. How many bouquets were sold today
Answer:
The answer is ten bouquets
Step-by-step explanation:
1 dozen is 12 if you were multiply 12 by 10 you would get 120. Now multiply 10 by twelve instead you get the same answer
Final answer:
When the price of each bouquet increased from $10 to $12, the flower stand sold 10 bouquets to make the same total sales of $120 as the previous day.
Explanation:
The question at hand involves a basic mathematical calculation of how changes in price affect the number of units sold to achieve the same total revenue. If a flower stand sold a dozen bouquets for $10 each yesterday, they made $120 in total sales (12 bouquets imes $10 per bouquet). Today, with the price increase to $12 per bouquet, we need to find out how many bouquets were sold to still make $120 in total sales. The calculation is as follows:
Total Sales = Number of Bouquets Sold imes Price per Bouquet
We know that the Total Sales should still be $120, and the Price per Bouquet is now $12. Therefore:
$120 = Number of Bouquets Sold imes $12
Number of Bouquets Sold = $120 / $12
Number of Bouquets Sold = 10 bouquets
Thus, the flower stand sold 10 bouquets today to make the same amount of money as yesterday after increasing the price to $12 each.
Find the circumference of the circle with the given radius. Round to the nearest tenth. Use 3.14 for π.
r = 8 cm
Step-by-step explanation:
Circumference of the circle= 2πr
=2×3.14×8 cm
= 50.24cm
= 50.2 cm
Answer:
50.27
rounded : 50.3
Step-by-step explanation:
2 times 3.14 times 8
hope this helped
brainliest is appreciated :)
Green paint is made by mixing 5 pints of blue paint and 2 pints of yellow paint.
How many pints of blue pints are neede to make 28 pints of green paint
Answer:
5 pints of blue and 2 pints of yellow make 7 pints of green. (5 + 2 = 7)
You must do this four times to get 28 pints of green. (4 · 7 = 28)
So you need 20 (4 · 5) pints of blue and 8 (4 · 2) pints of yellow.
Step-by-step explanation:
Answer:
140 pints
Step-by-step explanation:
An article in the Journal of Materials Engineering (Vol 11, No. 4, 1989, pp. 275-282) reported the results of an experiment to determine failure mechanisms for plasma-sprayed thermal barrier coatings. The failure stress for one particular coating (NiCrAlZr) under two different test conditions is as follows:
Failure stress ( times 10^6 Pa) after nine 1-hr cycles: 19.8, 18.5, 17.6,16.7, 16.7, 14.8, 15.4, 14.1, 13.6
Failure stress ( times 10^6 Pa) after six 1-hr cycles: 14.9, 12.7, 11.9, 11.4, 10.1,7.9
(a) What assumptions are needed to construct confidence intervals for the difference in mean failure stress under the two different test conditions? Use normal probability plots of the data to check these assumptions.
(b) Perform a hypothesis test to determine if the mean failure stress of the two different test conditions is the same at the 0.05 significance level.
(c) Confirm that the P-value of this test is 0.001.
Answer:
Step-by-step explanation:
Hello!
You have two variables of interest
X₁: failure stress of a NiCrAlZr coating after nine 1-hr cycles.
X₂: failure stress of a NiCrAlZr coating after six 1-hr cycles.
a)
To be able to estimate the difference between the means using a confidence interval, you need that both variables have a normal distribution and to determine whether or not the population variances are equal.
If the population variances are equal, σ₁²=σ₂², you can use a pooled variance t-test
If the population variances are different, σ₁²≠σ₂², you have to use Welch's t-test
Using α: 0.05
The normality test for X₁ shows a p-value of 0.7449 ⇒ You can assume it has a normal distribution.
The normality test for X₂ shows a p-value of 0.9980 ⇒ You can assume it has a normal distribution.
The F-test for variance homogeneity shows a p-value of 0.6968 (H₀:σ₁²=σ₂²) ⇒You can assume both population variances are equal.
b) and c)
You need to test if both population means are the same, the hypotheses are:
H₀: μ₁=μ₂
H₁: μ₁≠μ₂
α: 0.05
[tex]t= \frac{(X[bar]_1-X[bar]_2)-(Mu_1-Mu_2)}{Sa*\sqrt{\frac{1}{n_1} +\frac{1}{n_2} } } ~~t_{n_1+n_2-2}[/tex]
[tex]Sa= \sqrt{\frac{(n_1-1)S^2_1+(n_2-1)S^2_2}{n_1+n_2-2} } = \sqrt{\frac{8*4.28+5*5.62}{9+6-2} }= \sqrt{4.7953}= 2.189= 2.19[/tex]
[tex]t_{H_0}= \frac{(X[bar]_1-X[bar]_2)-(Mu_1-Mu_2)}{Sa*\sqrt{\frac{1}{n_1} +\frac{1}{n_2} } } = \frac{(16.36-11.48)-0}{2.19*\sqrt{\frac{1}{9} +\frac{1}{6} } } = 4.23[/tex]
The distribution of this test is a t with 13 degrees of freedom and the test is two-tailed, so to calculate the p-value you have to do the following:
P(t₁₃≤-4.23)+P(t₁₃≥4.23)= P(t₁₃≤-4.23)+[1-P(t₁₃<4.23)]= 0.000492 + (1-0.999508)= 2*0.000492= 0.000984≅ 0.001
The p-value: 0.001 is less than α: 0.05, the decision is to reject the null hypothesis.
I hope it helps!
The probability of winning an arcade game is 0.632 and the probability of losing is 0.368. If you play the arcade game 10 times, we want to know the probability of winning no more than 8 times. Consider winning as a success in the binomial distribution. Do not include p= in your answer.
The probability of winning no more than 8 times out of 10 plays of the arcade game is approximately 0.6394.
Here, we have,
To calculate the probability of winning no more than 8 times out of 10 plays of the arcade game, we need to find the cumulative probability of winning 0, 1, 2, 3, 4, 5, 6, 7, and 8 times.
We'll use the binomial distribution formula to do this:
The binomial distribution formula for a probability of k successes in n trials is given by:
[tex]P(X = k) = C(n, k) * p^k * (1 - p)^{(n - k)[/tex]
where:
P(X = k) is the probability of exactly k successes,
n is the total number of trials (10 in this case),
k is the number of successes we want to calculate the probability for (0 to 8 in this case),
p is the probability of winning (0.632 in this case),
C(n, k) is the binomial coefficient, calculated as
C(n, k) = n! / (k! * (n - k)!).
Now, let's calculate the probabilities for each value of k and then sum them up to find the cumulative probability:
P(X ≤ 8) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8)
now, we have,
[tex]P(X = 0) = C(10, 0) * (0.632)^0 * (1 - 0.632)^{(10 - 0)}\\P(X = 1) = C(10, 1) * (0.632)^1 * (1 - 0.632)^{(10 - 1)}\\P(X = 2) = C(10, 2) * (0.632)^2 * (1 - 0.632)^{(10 - 2)}\\P(X = 3) = C(10, 3) * (0.632)^3 * (1 - 0.632)^{(10 - 3)}\\P(X = 4) = C(10, 4) * (0.632)^4 * (1 - 0.632)^{(10 - 4)}\\[/tex]
[tex]P(X = 5) = C(10, 5) * (0.632)^5 * (1 - 0.632)^{(10 - 5)}\\P(X = 6) = C(10, 6) * (0.632)^6 * (1 - 0.632)^{(10 - 6)}\\P(X = 7) = C(10, 7) * (0.632)^7 * (1 - 0.632)^{(10 - 7)}\\P(X = 8) = C(10, 8) * (0.632)^8 * (1 - 0.632)^{(10 - 8)}[/tex]
Now, let's calculate each of these probabilities:
[tex]P(X = 0) = 1 * 1 * (0.368)^{10} = 0.0010434068\\P(X = 1) = 10 * 0.632 * (0.368)^9 = 0.0091045617\\P(X = 2) = 45 * 0.632^2 * (0.368)^8 = 0.0333533058\\P(X = 3) = 120 * 0.632^3 * (0.368)^7 = 0.0789130084\\P(X = 4) = 210 * 0.632^4 * (0.368)^6 = 0.1312387057\\P(X = 5) = 252 * 0.632^5 * (0.368)^5 = 0.1552134487\\P(X = 6) = 210 * 0.632^6 * (0.368)^4 = 0.1320219902\\P(X = 7) = 120 * 0.632^7 * (0.368)^3 = 0.0702045343\\P(X = 8) = 45 * 0.632^8 * (0.368)^2 = 0.0272837154\\[/tex]
Now, let's sum up these probabilities:
P(X ≤ 8) ≈ 0.0010434068 + 0.0091045617 + 0.0333533058 + 0.0789130084 + 0.1312387057 + 0.1552134487 + 0.1320219902 + 0.0702045343 + 0.0272837154
≈ 0.6393716762
So, the probability of winning no more than 8 times out of 10 plays of the arcade game is approximately 0.6394.
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Finally, we find:
P(X ≤ 8) ≈ P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8)
To calculate the probability of winning no more than 8 times out of 10 plays in the arcade game, we can use the binomial distribution.
The binomial distribution calculates the probability of having a certain number of successes (in this case, winning) in a fixed number of independent trials (10 plays) when the probability of success (p) remains constant.
Probability of winning (p) = 0.632
Probability of losing (q, since p + q = 1) = 0.368
Number of trials (n) = 10
To find the probability of winning no more than 8 times, we need to sum the probabilities of winning 0, 1, 2, 3, 4, 5, 6, 7, and 8 times.
P(X ≤ 8) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8)
Using the binomial probability formula:
P(X = k) = (n choose k) * p^k * q^(n-k)
where (n choose k) is the binomial coefficient, given by:
(n choose k) = n! / (k! * (n-k)!)
Calculating the probabilities for each individual case:
P(X = 0) = (10 choose 0) * (0.632^0) * (0.368^(10-0))
P(X = 1) = (10 choose 1) * (0.632^1) * (0.368^(10-1))
P(X = 2) = (10 choose 2) * (0.632^2) * (0.368^(10-2))
...
P(X = 8) = (10 choose 8) * (0.632^8) * (0.368^(10-8))
After calculating the probabilities for each individual case, we can sum them up to find P(X ≤ 8).
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2. Find the Area of the triangle.
as do
12 yd
15 yd
Given:
The base of the triangle = 15 yd
The height of the circle = 12 yd
To find the area of the triangle.
Formula
The area of the triangle is
[tex]A=\frac{1}{2} bh[/tex]
where, b be the base of the triangle
h be the height of the triangle
Now,
Putting, b= 15 and h=12 we get,
[tex]A=\frac{1}{2} (15)(12)[/tex] sq yd
or, [tex]A = 90[/tex] sq yd
Hence,
The area of the triangle is 90 sq yd.
Answer:
A =90 yd^2
Step-by-step explanation:
The area of a triangle is given by
A = 1/2 bh
A = 1/2(15)*12
A =90 yd^2
Can somebody help me please
NEED IT SOLVED ASAP ANSWER AS QUICKLY AS U CAN
Answer:
-121
Step-by-step explanation:
[tex] \frac{t}{ - 11} = 11 \\ t = - 11 \times 11 \\ \huge \red{ \boxed{t = - 121}}[/tex]
Given f(x) and g(x) = f(x + k), use the graph to determine the value of k. Two lines labeled f of x and g of x. Line f of x passes through points negative 4, 0 and negative 2, 2. Line g of x passes through points negative 10, 0 and negative 8, 2.
Answer:
Sorry about that answer, some people are plain rude, but the correct answer is -5.
Step-by-step explanation:
Hope this Helps! Good Luck!
Answer: k=-5 is correct because if you were to divide -10/-2 it would give you -5
I hope this simplifies your question for the answer.
Identify the value for the variable.
What is the value of x in this simplified expression?
7-9 · 7-3 = 7x
x =
What is the value of y in this simplified expression?
StartFraction 11 Superscript negative 4 Baseline Over 11 Superscript negative 8 Baseline EndFraction = 11 Superscript y
y =
Answer:
x= -12 y= 4
Step-by-step explanation:
Answer:
Y=4
x=-12
Step-by-step explanation:
Suppose the number of inches of rainfall each year in a city is normally distributed. For a random sample of years, the confidence interval (3.9,7.7) is generated. Find the margin of error
Answer:
The confidence interval for the mean is given by the following formula:
[tex]\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex] (1)
Or equivalently:
[tex]\bar X \pm ME[/tex]
For this case we have the interval given (3.9, 7.7) and we want to find the margin of error. Using the property of symmetry for a confidence interval we can estimate the margin of error with this formula:
[tex]ME= \frac{Upper -Lower}{2}= \frac{7.7-3.9}{2}= 1.9[/tex]
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
[tex]\bar X[/tex] represent the sample mean for the sample
[tex]\mu[/tex] population mean (variable of interest)
Solution to the problem
The confidence interval for the mean is given by the following formula:
[tex]\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex] (1)
Or equivalently:
[tex]\bar X \pm ME[/tex]
For this case we have the interval given (3.9, 7.7) and we want to find the margin of error. Using the property of symmetry for a confidence interval we can estimate the margin of error with this formula:
[tex]ME= \frac{Upper -Lower}{2}= \frac{7.7-3.9}{2}= 1.9[/tex]
An experienced ice skater spins on the ice, creating a perfect circle with a diameter of 8 feet. What is the circles radius?
Answer:
radius-4
Step-by-step explanation:
the radius is half of the diameter
State the conclusion based on the results of the test. The standard deviation standard deviation in in the pressure required to open a certain valve is known to be sigma equals 1.1 psi. σ=1.1 psi. Due to changes in the manufacturing process, the quality-control manager feels that the pressure pressure variability variability has changed changed. The null hypothesis was not rejected not rejected. Choose the correct answer below. A. There is is sufficient evidence that the standard deviation standard deviation in in the pressure required to open a certain valve has changed changed. B. There is is sufficient evidence that the standard deviation standard deviation in in the pressure required to open a certain valve has not changed. C. The standard deviation standard deviation in in the pressure has not changed. D. There is not is not sufficient evidence that the standard deviation standard deviation in in the pressure required to open a certain valve has not changed. E. There is not is not sufficient evidence that the standard deviation standard deviation in in the pressure required to open a certain valve has changed changed. F. The standard deviation standard deviation in in the pressure has changed changed.
Answer:
B
Step-by-step explanation:
Null hypothesis is not rejected if the test statistics show that the difference between observed and expected value is not significant and any difference is only due to chance.
So there is sufficient evidence from statistics that null hypothesis is true and the standard deviation in the pressure required to open a certain valve has not changed.
since evidence has to be there when null hypothesis is tested, optionC, D and E are rejected.
There is no change in standard deviation so option A and F are rejected.
. upper left chamber is enlarged, the risk of heart problems is increased. The paper "Left Atrial Size Increases with Body Mass Index in Children" (International Journal of Cardiology [2009]: 1–7) described a study in which the left atrial size was measured for a large number of children age 5 to 15 years. Based on this data, the authors concluded that for healthy children, left atrial diameter was approximately normally distributed with a mean of 26.4 mm and a standard deviation of 4.2 mm. (a) Approximately what proportion of healthy children have left atrial diameters less than 24 mm? (b) Approximately what proportion of healthy children have left atrial diameters between 25 and 30 mm? (c) For healthy children, what is the value for which only about 20% have a larger left atrial diameter? [4] Suppose that the mean value of interpupillary distance (the distance between the pupils of the left and 2. right eyes) for adult males is 65 mm and that the population standard deviation is 5 mm. Suppose that a random sample of 100 adult males is to be obtained. (a) what is the probability that the sample mean distance ¯x for these 100 will be between 64 and 67 mm?
Answer:
Part 1
(a) 0.28434
(b) 0.43441
(c) 29.9 mm
Part 2
(a) 0.97722
Step-by-step explanation:
There are two questions here. We'll break them into two.
Part 1.
This is a normal distribution problem healthy children having the size of their left atrial diameters normally distributed with
Mean = μ = 26.4 mm
Standard deviation = σ = 4.2 mm
a) proportion of healthy children have left atrial diameters less than 24 mm
P(x < 24)
We first normalize/standardize 24 mm
The standardized score for any value is the value minus the mean then divided by the standard deviation.
z = (x - μ)/σ = (24 - 26.4)/4.2 = -0.57
The required probability
P(x < 24) = P(z < -0.57)
We'll use data from the normal probability table for these probabilities
P(x < 24) = P(z < -0.57) = 0.28434
b) proportion of healthy children have left atrial diameters between 25 and 30 mm
P(25 < x < 30)
We first normalize/standardize 25 mm and 30 mm
For 25 mm
z = (x - μ)/σ = (25 - 26.4)/4.2 = -0.33
For 30 mm
z = (x - μ)/σ = (30 - 26.4)/4.2 = 0.86
The required probability
P(25 < x < 30) = P(-0.33 < z < 0.86)
We'll use data from the normal probability table for these probabilities
P(25 < x < 30) = P(-0.33 < z < 0.86)
= P(z < 0.86) - P(z < -0.33)
= 0.80511 - 0.37070 = 0.43441
c) For healthy children, what is the value for which only about 20% have a larger left atrial diameter.
Let the value be x' and its z-score be z'
P(x > x') = P(z > z') = 20% = 0.20
P(z > z') = 1 - P(z ≤ z') = 0.20
P(z ≤ z') = 0.80
Using normal distribution tables
z' = 0.842
z' = (x' - μ)/σ
0.842 = (x' - 26.4)/4.2
x' = 29.9364 = 29.9 mm
Part 2
Population mean = μ = 65 mm
Population Standard deviation = σ = 5 mm
The central limit theory explains that the sampling distribution extracted from this distribution will approximate a normal distribution with
Sample mean = Population mean
¯x = μₓ = μ = 65 mm
Standard deviation of the distribution of sample means = σₓ = (σ/√n)
where n = Sample size = 100
σₓ = (5/√100) = 0.5 mm
So, probability that the sample mean distance ¯x for these 100 will be between 64 and 67 mm = P(64 < x < 67)
We first normalize/standardize 64 mm and 67 mm
For 64 mm
z = (x - μ)/σ = (64 - 65)/0.5 = -2.00
For 67 mm
z = (x - μ)/σ = (67 - 65)/0.5 = 4.00
The required probability
P(64 < x < 67) = P(-2.00 < z < 4.00)
We'll use data from the normal probability table for these probabilities
P(64 < x < 67) = P(-2.00 < z < 4.00)
= P(z < 4.00) - P(z < -2.00)
= 0.99997 - 0.02275 = 0.97722
Hope this Helps!!!
Figure ABCD is a parallelogram.
What are the lengths of line segments AB and BC?
3
-2
в
• AB = 4, BC = 16
AB = 4; BC = 8
AB = 10; BC = 20
• AB = 10; BC = 28
y
+
6
Given:
Given that ABCD is a parallelogram.
The length of AB is 3y - 2.
The length of BC is x + 12.
The length of CD is y + 6.
The length of AD is 2x - 4.
We need to determine the length of AB and BC.
Value of y:
We know the property that opposite sides of a parallelogram are congruent, then, we have;
[tex]AB=CD[/tex]
Substituting the values, we get;
[tex]3y-2=y+6[/tex]
[tex]2y-2=6[/tex]
[tex]2y=8[/tex]
[tex]y=4[/tex]
Thus, the value of y is 4.
Value of x:
We know the property that opposite sides of a parallelogram are congruent, then, we have;
[tex]AD=BC[/tex]
Substituting the values, we get;
[tex]2x-4=x+12[/tex]
[tex]x-4=12[/tex]
[tex]x=16[/tex]
Thus, the value of x is 16.
Length of AB:
The length of AB can be determined by substituting the value of y in the expression 3y - 2.
Thus, we have;
[tex]AB=3(4)-2[/tex]
[tex]=12-2[/tex]
[tex]AB=10[/tex]
Thus, the length of AB is 10 units.
Length of BC:
The length of BC can be determined by substituting the value of x in the expression x + 12.
Thus, we have;
[tex]BC=16+12[/tex]
[tex]BC=28[/tex]
Thus, the length of BC is 28 units.
Hence, the length of AB and BC are 10 units and 28 units respectively.
If y varies directly as x, find k if y = 27 and x = 3.
Answer:
k=9
Step-by-step explanation:
The formula for direct variation is
y = kx
We know y and x
27 = k*3
Divide each side by 3
27/3 = 3k/3
9 =k
A person measures the contents of 25 pop cans and finds the mean content to be 12.1 fluid ounces with a standard deviation of 0.2 ounces. Construct a 99% confidence interval for the average fluid content of a can.
Answer:
The 99% confidence interval for the average fluid content of a can is between 11.54 and 12.66 fluid ounces.
Step-by-step explanation:
We are in posession of the sample's standard deviation, so we use the student t-distribution to solve this question.
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 = 25 - 1 = 24
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995([tex]t_{995}[/tex]). So we have T = 2.797
The margin of error is:
M = T*s = 2.797*0.2 = 0.56
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 12.1 - 0.56 = 11.54 fluid ounces.
The upper end of the interval is the sample mean added to M. So it is 12.1 + 0.56 = 12.66 fluid ounces.
The 99% confidence interval for the average fluid content of a can is between 11.54 and 12.66 fluid ounces.
Solve: 18^x^2+4x+4 = 18^9x+18
Answer:
x = -2 or +7
Step-by-step explanation:
We presume you want to solve ...
18^(x^2 +4x +4) = 18^(9x +18)
Equate exponents of the same base and put the quadratic in standard form.
x^2 +4x +4 = 9x +18
x^2 -5x -14 = 0
(x -7)(x +2) = 0
Values of x that make these factors zero are 7 and -2.
The solutions are x=-2 or x = 7.
Answer:
c
Step-by-step explanation:
got it right on edge
2/3 divided by blank equals