Re: HELP!!
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where did u get the 46 from?
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Since we are choosing 2, the numerator has 2 terms counting backwards from 47, so it is 47*46. This comes from the fact that C(47,2) = 47!/(47-2)!/2! = 47!/45!/2!, and since 47! = 47*46*45!, the 45! cancels out to give 47*46/2!.
Here are a couple more examples:
C(47,3) = 47*46*45/(3*2*1)
C(52,5) = 52*51*50*49*48/(5*4*3*2*1)
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