If a committee of 3 people is to be selected from among 5 married couples so that the committee does not include two people who are married to each other, how many X such committees are possible? Select the correct option.
A) X=20  B) X=40  C) X=50  D) X=80  E) 120
Each couple can send only onerepresentativeto the committee. Let's see in how many ways we can choose 3 couples (as there should be 3 members) each to send onerepresentativeto the committee: 5C3=10.   But these 3 chosen couples can send two persons (either husband or wife): 2*2*2=2^3=8.   Total # of ways: 5C3*2^3=80.   Answer: X=80.
<result>D</result>
If a committee of 3 people is to be selected from among 5 married couples so that the committee does not include two people who are married to each other, how many X such committees are possible?