Bunuel
At a certain university, 7 students from the 10-student history department and 5 students from the 7-student English department will be selected to form a 12-student committee. At a neighboring university, 2 students from a 10-person math department and 3 students from a 7-student science department will be selected to form a 5-student focus group. What is the ratio of the number of ways in which the 12-student committee can be formed to the number of ways in which the 5-student focus group can be formed?
A. 25/16
B. 8/5
C. 12/5
D. 16/5
E. 144/25
We can start with the first university:
10C7 = 10!/(7! x 3!) = (10 x 9 x 8)/(3 x 2) = 120
7C5 = 7!/(5! x 2!) = (7 x 6)/2 = 21
Thus, number of ways the 12-student committee can be formed at the first university is 120 x 21.
Now, for the second university:
10C2 = 10!/(8! x 2!) = (10 x 9)/2 = 45
7C3 = 7!/(4! x 3!) = (7 x 6 x 5)/(3 x 2) = 35
Thus, the number of ways the 5-student focus group can be formed at the second university is 45 x 35.
Therefore, the ratio is (120 x 21)/(45 x 35) = (15 x 8 x 3 x 7)/(15 x 3 x 5 x 7) = 8/5.
Answer: B