Prior to the institution of a new safety program, the average number of on-the-job accidents per day at a factory was 4.5. To determine if the safety program has been effective in reducing the average number of accidents per day, a random sample of 30 days is taken after the institution of the new safety program and the number of accidents per day is recorded. The sample mean and standard deviation were computed as follows: Sample mean = 3.7, standard deviation = 1.3 a. Is there sufficient evidence to conclude that the average number of on-the-job accidents per day at the factory has decreased since the institution of the safety program? b. What is the practical interpretation

Prior to the institution of a new safety program, the average number of on-the-job accidents per day at a factory was 4.5. To determine if the safety program has been effective in reducing the average number of accidents per day, a random sample of 30 days is taken after the institution of the new safety program and the number of accidents per day is recorded. The sample mean and standard deviation were computed as follows: Sample mean = 3.7, standard deviation = 1.3 a. Is there sufficient evidence to conclude that the average number of on-the-job accidents per day at the factory has decreased since the institution of the safety program? b. What is the practical interpretation

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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