Arthur D. answered 03/02/15
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how many ways can you choose 5 males from a group of 15 males ?
15!/(5!)(15-5)!
15!/(5!)(10!)
(15*14*13*12*11)/(5*4*3*2)
simplifying...
3*7*13*11=3003 ways (15/5=3, 12/4*3=1, 14/2=7)
how many ways can you choose 4 females from a group of 10 females ?
10!/(4!)(10-4)!
10!/(4!)(6!)
(10*9*8*7*)/(4*3*2)
simplifying...
10*3*7=210 ways (9/3=3, 8/4*2=1)
each group of 5 males can be paired with each group of 4 females
there are 3003 groups of males and 210 groups of females
3003*210=630,630 choices of 5 males and 4 females