If you know expected value is 500 and the standard deviation is 12

posted 10months ago by Natalie2000
© Copyright: Project Management Professional (PMP) Study Guide by Kim Heldman, Sybex Inc., Alameda, CA, USA, 2002, page 280, question 10
Earned Value Analysis | Standard Deviation

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

A. The activity will take between 488 and 512 days.
B. The activity will take between 464 and 536 days.
C. The activity will take between 494 and 506 days.
D. The activity will take between 476 and 524 days.