. (on a paper) A certain type of automobile battery is known to last an average of 1110 days with a standard deviation of 80 days. If 400 of these batteries are selected, find the following probabilities for the average length of life of the selected batteries (Hint: What is the sampling distribution of the sample mean?): 1. The average is between 1100 and 1110. 2. The average is greater than 1120. 3. The average is less than 900.

. (on a paper) A certain type of automobile battery is known to last an average of 1110 days with a standard deviation of 80 days. If 400 of these batteries are selected, find the following probabilities for the average length of life of the selected batteries (Hint: What is the sampling distribution of the sample mean?): 1. The average is between 1100 and 1110. 2. The average is greater than 1120. 3. The average is less than 900.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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