Four bells begin to toll together respectively at the intervals of 8, 10, 12 and 16 seconds. After how many seconds will they toll together again?

A. 36
B. 81
C. 91
D. 116
Explanation:
When the dice are rolled, the number of possible outcomes = 63 = 216.
Number of possible outcomes in which 2 does not appear on any dice = 53 = 125.
Therefore, Number of possible outcomes in which at least one dice shows 2 = 216- 125 = 91.