Posted by Celee on Tuesday, November 15, 2011 at 4:52pm.
3 cases :
2 women, 2 men ---> C(7,2)xC(5,2) = 21(10) = 210
3 women, 1 man ---> C(7,3)xC(5,1) = 35(5) = 175
4 women, 0 men ---> C(7,4) = 35
add up the 4 cases to get 420
or, exclude the case of no women, and one woman
C(12,4) - C(7,1)xC(5,3) - C(7,0)x(C5,4)
= 495 - 70 - 5 = 420