3. In rolling a pair of dice, find the probability of not rolling a sum of 7.
A. 1/36
B. 5/36
C. 5/6
D. 5/12
The probability of not rolling a 7 on any one roll is 5/6. The probability of not rolling a 7 in 28 rolls is
(5/6)28 = 0.006066, or about 1 in 165.