SOLUTION: Fond 15c7by hand show work

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Question 549841: Fond 15c7by hand show work
Found 3 solutions by jim_thompson5910, mathie123, Alan3354:
Answer by jim_thompson5910(35256) About Me  (Show Source):
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(n!)/(r!(n-r)!)

(15!)/(7!*(15-7)!)

(15!)/(7!*8!)

(15*14*13*12*11*10*9*8!)/(7!*8!)

(15*14*13*12*11*10*9)/(7!)

(15*14*13*12*11*10*9)/(7*6*5*4*3*2*1)

(32432400)/(5040)

6435


So 15 C 7 = 6435

Answer by mathie123(224) About Me  (Show Source):
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nCr=%28n%21%29%2F%28r%21%28n-r%29%21%29 by definition
15C7=%2815%21%29%2F%287%21%2815-7%29%21%29
%2815%21%29%2F%287%218%21%29

Now does anything divide out from the top and bottom?(numerator and denominator)
%2815%2A14%2A13%2A12%2A11%2A10%2A9%29%2F%287%2A6%2A5%2A4%2A3%2A2%2A1%29
And now is there any common factors we can divide out? (for example 14=2*7 and we have a 7 in the denominator so we can cancel a 7 from both those numbers)
%283%2A13%2A11%2A5%2A3%29
6435
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Hopefully this helps!
Romans 5:8

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Leviticus 20:9 too.