What is the estimated standard deviation in the time for activity E?
A)0 weeks
B)1 week
C)2 weeks
D)3 weeks
E)4 weeks

Question

Quizplus · Accepted Answer

The estimated standard deviation for activity E can be calculated using the formula:
σ = (𝑎 − 𝑚)/6 
where a is the optimistic time, m is the most likely time, and σ is the standard deviation.

From the chart, we can see that the optimistic time for activity E is 2 weeks, the most likely time is 4 weeks, and the pessimistic time is 6 weeks. 
Therefore, σ = (6-2)/6 = 0.67 weeks.

However, since the options only provide whole numbers, the closest choice is C) 2 weeks.

What Is the Estimated Standard Deviation in the Time for Activity