### Understanding Confidence Intervals in Statistics**Problem Statement:**A recent study of 25 students showed that they spend an average of $18.53 for gas per week. The sample standard deviation was $3.00, and the sample distribution was approximately normal. If we were to find a 95% confidence interval for the true mean, it would be:**Options:**- a confidence interval for the mean using a table value from the standard normal distribution.- a confidence interval for the mean using a table value from the t distribution.- a confidence interval for a proportion using a table value from the standard normal distribution.- a confidence interval for a proportion using a table value from the t distribution.- none of the other answers are correct.**Explanation:**Given the sample size is 25, which is less than 30, and considering that we are dealing with a sample standard deviation instead of the population standard deviation, the appropriate method to calculate the confidence interval for the mean would be to use a table value from the t distribution.In this context:- **Standard Normal Distribution** is typically used when the sample size is large (n > 30).- **t Distribution** is more appropriate for smaller sample sizes (n ≤ 30) and when the population standard deviation is unknown.Therefore, the correct option is:- a confidence interval for the mean using a table value from the t distribution.

Given: Sample size n = 25 Sample mean X = 18.53 Sample standard deviation s = 3

Answered: A recent study of 25 students showed…

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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