A class contains five juniors and five seniors. If one member of the class is assigned at random to present a paper on a certain subject, and another member of the class is randomly assigned to assist him, what is the probability W that both will be juniors? Choose the correct choice from the following answers
A) 1/10
B) 1/5
C) 2/9
D) 2/5
E) 1/2
I think you're right. The other way to do it (but the long way) is to figure out the probability that it is not two Juniors.   2 seniors = P(Senior) * P(Senior) = 2/9   1 Senior and 1 Junior = (1/2) *(5/9)*2 = 5/9   Probability that it is not two Juniors is 5/9+2/9 = 7/9 so the probability W that it is two juniors is 1- (7/9) = 2/9.2/9
<result>C</result>
A class contains five juniors and five seniors. If one member of the class is assigned at random to present a paper on a certain subject, and another member of the class is randomly assigned to assist him, what is the probability W that both will be juniors?