Set S is the prime integers between 0 and 45. If three numbers are chosen randomly from set S, what is the probability that the sum of these three numbers is odd?  Choose the correct option:  A) 15/56  B) 3/8  C) 15/28  D) 5/8  E) 11/14
Total number of combinations=14C3=364...............(1)   Total number of combinations including 2 and two other numbers=13C2=78......................(2)   Therefore the difference ie. (1)-(2) is the set of 3 primes without 2=(364-78)= 
<gadget id="calculator">(364-78)</gadget>
<output>286</output>
286   So, probability=286/364=11/14   11/14
<result>E</result>
Set S is the prime integers between 0 and 45. If three numbers are chosen randomly from set S, what is the probability that the sum of these three numbers is odd?