Question 293441
Hello, 
The formula is nPr=n!/(n-r)!
So it would look like this:
15!/(15-3)! This expands out to:
(15x14x13x12x11x10x9x8x7x6x5x4x3x2x1)/(12x11x10x9x8x7x6x5x4x3x2x1)
I'll let you do the calculations from here. 
Make sense?
RJ
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