Question

Yoonie is a personnel manager in a large corporation. Each month she must review 16 of the employees. From past experience, she has found that the reviews take her approximately four hours each to do with a population standard deviation of 1.2 hours. (1) What is the mean time to complete one review? QUESTION 2 (2) What is the standard deviation to complete one review? QUESTION 3 (3) What is the probability that one review will take Yoonie from 3.5 to 4.25 hours? (Round to 3 decimal places) QUESTION 4 What is the mean for average time for Yoonie to complete the 16 reviews? QUESTION 5 (5) What is the standard deviation for her average time to complete the 16 reviews?

Answer 1

Answer Date: 10/11/2019 1) The mean of time to complete one review is, la = = 4 The mean of time to complete one review is 4. 2) The standard deviation of time to complete one review is, _ 1.20 = 1.20 The standard deviation of time to complete one review is 1.20.

3) The probability is that one review take Yoonie from 3.50 to 4.25 hours is, First, compute the z score then find probability based on standard normal table. For x = 3.50 converts to 2x-u 3.50 – 4.00 1.20 =-0.4167 For x = 4.25 converts to 4.25 -4.00 1.20 = 0.2083

From the standard normal distribution table, the associated probability for z values and subtracts the probability is, p(3.50 SX S4.25) = P(-0.4167 SzS0.2083) = P(Z < 0.2083) - P(Z S-0.4167) = 0.5825 - 0.3384 = 0.2441 = 0.244 The probability is that one review take Yoonie from 3.50 to 4.25 hours is 0.244. The mean for the average for Yoonie to complete 16 reviewers is, Hz = u = 4 The mean for the average for Yoonie to complete 16 reviewers is 4. S)

The standard deviation for the average for Yoonie to complete 16 reviewers is, - 1.20 -T16 =0.30 The standard deviation for the average for Yoonie to complete 16 reviewers is 0.30.