SOLUTION: nC(r-1)=56 nCr=28 nC(r+1)=8 what is the value of r?

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Question 636761: nC(r-1)=56
nCr=28
nC(r+1)=8
what is the value of r?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

nC(r-1)=56

 8C5 = 56   r = 6

and...

8C6 = 28  & 8C7 = 8