SOLUTION: Hi, I'm having trouble with the following problem: There are 7 boys and 5 girls in the debate squad at Franklin High School. In how many ways can a 4-member debating team be sel

Algebra ->  Permutations -> SOLUTION: Hi, I'm having trouble with the following problem: There are 7 boys and 5 girls in the debate squad at Franklin High School. In how many ways can a 4-member debating team be sel      Log On


   



Question 915421: Hi, I'm having trouble with the following problem:
There are 7 boys and 5 girls in the debate squad at Franklin High School. In how many ways can a 4-member debating team be selected:
a. If there are no restrictions? (I found this one: C(12,4) = 495)
b. If 2 boys and 2 girls must be on the team? (I found this one too: C(7,2) x C(5,2) = 210
c. If at least two boys must be on the team? (I can't figure out how to set this one up.)
Help!! For C., I have tried multiple ways of working out the problem, but I need help with how to set it up. I know for C. is 420.
Thank you!

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
choosing 4
c. choosing at lest 2 boys:
+%287C2%29%285C2%29+%2B+%287C3%29%285C1%29+%2B+%287C4%29%285C0%29 = 210 + 175 + 35 = 420