The Time Required to Complete a Project Is Normally Distributed

Multiple Choice

The time required to complete a project is normally distributed with a mean of 80 weeks and a standard deviation of 10 weeks.The construction company must pay a penalty if the project is not finished by the due date in the contract.If a construction company bidding on this contract wishes to be 90 percent sure of finishing by the due date, what due date (project week #) should be negotiated?

A) 81.28
B) 92.8
C) 81.82
D) .81954