Table A2
-For this question,please use the standard normal distribution table,Table A2.It has been estimated that the mean time required to complete a project is 20 weeks and the variance of project completion time is 9 weeks.What is the probability that the project will be completed in 23 weeks?
A)34%
B)50%
C)68%
D)84%

Question

Table A2
-For this question,please use the standard normal distribution table,Table A2.It has been estimated that the mean time required to complete a project is 20 weeks and the variance of project completion time is 9 weeks.What is the probability that the project will be completed in 23 weeks?
A)34% 
B)50% 
C)68% 
D)84%

Quizplus · Accepted Answer

To find the probability that the project will be completed in 23 weeks, we first calculate the Z-score using the formula Z = (X - μ) / σ, where X is the value of interest (23 weeks), μ is the mean (20 weeks), and σ is the standard deviation (√variance = √9 = 3 weeks). Thus, Z = (23 - 20) / 3 = 1. The standard normal distribution table (Table A2) shows that the probability of a Z-score being less than 1 is approximately 0.8413, or 84%. This means there's an 84% chance the project will be completed in 23 weeks or less.

Table A2 -For This Question,please Use the Standard Normal Distribution Table,Table A2.It