If you know that the expected value is 500 and the standard deviation is 12, you can say with approximately a 95% confidence rating which of the following?

95% means +/-2 sigma, the activity will take between 500+12*2 and 500-12*2, D is the answer

The figures in question do not exist ??

But here's the equation

Kashinath Bansode  is given correct Answer

Explanation:

There is a 95 percent probability that the work will finish within plus or minus two standard

deviations. The expected value is 500, and the standard deviation times 2 is 24, so the activity will

take from 476 to 524 days.

There is 95% probability that the work will finish within plus or minus two standard deviation. The expected value is 500, & the standard deviation time 2 is 24, so the activity will take from 476 to 524 days.

Simple , activity will take from 488 days ( 500 - 12 ) to 512 days ( 500 + 12 )  & thanks for the invite.

Thanks for the invitation. Sorry I do not know the exact answer.