A researcher wants to estimate the average time a person spends commuting to Boston. The researcher chooses a random sample of 22 people and finds that their average commute is 49 minuteswith a standard deviation of 19 minutes. Assume that commute times are normally distributed.(a) Why are we allowed to assume that the sampling distribution in this problem is approximately normal?O The margin of error is unknown.O The population standard deviation is known.O The population is normally distributed.O The sample size is large enough.(b) Which distribution should be used to find the critical value?O The t-distribution because o is unknown.O The t-distribution because the sample size is small.O The Z-distribution because o is known.O The z-distribution because the sample mean is large enough.(c) Construct a 90% confidence interval for the true average commute time. Round your answers to two decimal places.lower limitupper limitmargin of error

Given: Sample size, n is 22 Sample mean, x¯=49 Sample sd, s is 19

Answered: (a) Why are we allowed to assume that…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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find normal distribution P(1 < Z < 2) = P(Z < 2) − ____________________.
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