If three distinct positive divisors of 128 are randomly selected, what is the probability that their sum will be less than 64?
Choose the most appropriate option
A) 1/3 B) 3/7 C) 5/14 D) 9/28 E) 21/56
The positive divisors are 1, 2, 4, 8, 16, 32, 64, 128.   If any of the first six are chosen, the sum will be less than 64.   P(sum is less than 64) = 6/8 * 5/7 * 4/6 = 20/56 = 5/14   The answer is 5/14.
<result>C</result>
If three distinct positive divisors of 128 are randomly selected, what is the probability that their sum will be less than 64?