Answer: 8 hours
Using only three activity time estimations, the expected time for this job can be estimated using a mean or a median. If we use the mean, we add 3 estimates ((6,8 and (16+8)) and divide the sum by 3 (equals 13). If we use the median, expected time is 8 hours. In this case, where have extreme estimates, it is better to use the median, the number halfway in to the set which is 8.