Question

If the mean time between in-flight aircraft engine shutdowns is 12,500 operating hours, the 90th percentile of waiting times to the next shutdown will be:

Answer 1

To determine the 90th percentile of waiting times to the next shutdown, we use the formula 
(10)* E[X] = 2.30258509*E[X] 2.30258*12500 =  28782.31 HOURSTherefore, the 90th percentile of waiting times to the next shutdown will be approximately 28782 hours