4. An app developer would like to know how many songs people put in their phones. He interviewed 25 of them and found that they have 34.5 songs on average with a sample standard deviation of 3.4 songs. With a confidence level of 90%, determine the confidence interval estimate of the population mean.

Q: A survey was conducted that asked 1017 people how many books they had read in the past year. Results…

A: In the problem, the following are given:xˉ=12.8; The mean number of books the respondents read in…

Q: Determine the point estimate of the population mean and margin of error for the confidence interval.…

A: Given, Lower bound = 18  upper bound = 26

Q: If a 92% Confidence Interval for the Population Mean is (67.8, 78.9), find its Margin of Error.

A:

Q: y selected textbooks' weights, and find they have a mean weight of 78 ounces. Assume the population…

A: As the population standard deviation is known, we will use z distribution. The value of z at 95%…

Q: Suppose you select a random sample of N=81, and find X = 50, and s = 9.9. Determine the 99%…

A: Given Mean=50 Standard deviations=9.9 n=81

Q: Suppose we wanted to estimate the average amount of sleep (in hours) a college student gets a night.…

A: Confidence interval : Confidence interval is a range of values it contains the true population…

Q: Suppose we take a survey of 200 students and ask how much they study per week. The result is an…

A: From the above data  We are given that the  95% confidence interval is (10, 10.5). The population…

Q: Suppose that a 92% Confidence Interval for estimating the average heights, in inches, of all college…

A: confidence interval = x ± margin of errorlower limit = x - margin of errorupper limit = x + margin…

Q: If a school district takes a random sample of 75 Math SAT scores and finds that the average is 433,…

A:

Q: what would the 95% confidence limits for a sample of 120 with a mean of 51 and a standard deviation…

A: It is given that mean and standard deviation are 51 and 12, respectively.

Q: he average weight of 20 randomly selected cars was 3500 pounds. The sample standard deviation was…

A: given data, n=20df=n-1=20-1=19x¯=3500 pounds s=315 pounds CI=0.90α=1-0.90=0.10

Q: e confidence interval for a population mean is (240.53, 240.79). What are the sample mean and the…

A: The confidence interval for a population mean is (240.53, 240.79)WE HAVE TO FIND OUT THE MEAN AND…

Q: You measure 43 randomly selected textbooks' weights, and find they have a mean weight of 33 ounces.…

A: We have to find 95% confidence interval for the true population mean textbook weight.

Q: If n=540 and (p-hat) = 0.13, construct a 99% confidence interval. Give your answers to three…

A: We have given that,  Sample size (n) = 540  Sample proportion (p-hat) = 0.13 Then,  We will find the…

Q: You measure 49 backpacks' weights, and find they have a mean weight of 69 ounces. Assume the…

A: Solution:Given information:

Q: If n=590 and p=0.93, construct a 90% confidence interval.

A: Express the expression for the confidence interval. C.I=p±Z*p(1-p)n Here, Z* is the critical value .…

Q: ou measure 46 dogs' weights, and find they have a mean weight of 32 ounces. Assume the sample…

A:

Q: If a school district takes a random sample of 80 Math SAT scores and finds that the average is 497,…

A:

Q: If a school district takes a random sample of 89 Math SAT scores and finds that the average is 497,…

A: From the provided information, Sample size (n) = 89 Sample mean (x̅) = 497 Population standard…

Q: You measure 45 watermelons' weights, and find they have a mean weight of 56 ounces. Assume the…

A: The random variable weight follows normal distribution. The sample size is 45. The sample mean is…

Q: Find a 95% confidence interval for the difference between full attendance students' Exam 5 score and…

A: We have given data,  Less attendance Full attendance 90 96 90 96 60 100 50 99 69   88…

Q: You measure 29 backpacks' weights, and find they have a mean weight of 46 ounces. Assume the…

A:

Q: If Xbar=93​, σ=13​, and n=62​, construct a 99​% confidence interval estimate of the population​…

A: Given that  Sample size: n=62 Sample mean: x¯=93 Population standard deviation: σ=13 Confidence…

Q: If a school district takes a random sample of 89 Math SAT scores and finds that the average is 494,…

A:

Q: n = 480 and X = 384, construct a 90% confidence interval for the population proportion, p. Give…

A: Here is given that, n =480   x = 384 We will use one proportion  z confidence interval.

Q: You receive a brochure from a large university. The brochure indicates that the mean class size for​…

A: Sample size is, Population mean is Confidence Level is The objective is to test the claim that the…

Q: A sociologist develops a test to measure attitudes about public transportation, and 27 randomly…

A: Given,sample size(n)=27sample mean(x¯)=76.2standard deviation(s)=21.4degrees of…

Q: confidence interval for a population mean is (56,78), with a margin of error of 11. What is the…

A: From provided information, Confidence interval for population mean is (56, 78), with margin of error…

Q: A credit counseling agency wants to estimate the mean amount of credit card debt held by Americans.…

A: Here we need to construct a 90% confidence interval for the population mean.

Q: Suppose we take a survey of 400 students and ask how much they study per week. The result is an…

A: The 100 (1 – α)% confidence interval provides an interval estimation of the required population…

Q: If N=480 and p̂ (p-hat) =0.88, find the margin of error at a 95% confidence level.

A: From the provided information, Sample size (n) = 480 p̂ (p-hat) =0.88 Confidence level = 95%

Q: At the local fish hatchery we take a random sample of 21 trout from one of the holding pens.  The…

A:

Q: A small business wanted to estimate the mean income from their customers. They took a sample of 256…

A: We have to find  the 90% confidence interval estimate for the population mean income of their…

Q: second-semester junior at a large high school wants to estimate the number of colleges a senior…

A: Solution