Answered: random sample of 81 automobiles…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Related questions

Question

Exhibit 8-3. A random sample of 81 automobiles traveling on a section of an interstate showed an average speed of 60 mph. The distribution of speed of all cars on this section of highway is normally distributed, with a standard deviation of 13.5 mph.

If we are interested in determining an interval estimate for µ at 86.9% confidence, the z value to use is _____.

I know the answer is 1.51 but I do not understand how to arrive at this answer.

Features Features Normal distribution is characterized by two parameters, mean (µ) and standard deviation (σ). When graphed, the mean represents the center of the bell curve and the graph is perfectly symmetric about the center. The mean, median, and mode are all equal for a normal distribution. The standard deviation measures the data's spread from the center. The higher the standard deviation, the more the data is spread out and the flatter the bell curve looks. Variance is another commonly used measure of the spread of the distribution and is equal to the square of the standard deviation.

Expert Solution