Permutations and Combinations

Question

From a group of 3 accountants, 4 doctors and 5 lawyers a sub-committee of four people

is selected at random. Find the probability that the sub-committee will consist of 2

accountants and 2 lawyers.?

Answer 1

C(3,2)*C(5,2)*(4,0)

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C(12,4)

where C(x,y) combinations of x items, taken y a a time = x!/y!(x-y)!