railway RRB JE (CBT I + CBT II) Mock Test 2024 Industrial Engineering Operations Research PERT and CPM
The optimistic, most likely and pessimistic time of an activity are 6, 9 and 12 days respectively. The standard deviation and variance of the activity are ________ respectively.
1
1 and 2
2
1 and 1
3
2 and 1
4
2 and 2