Question 1136688
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(n+1)C(n-1) is the same as (n+1)C(2).  Then the equation is 8*((n+1)C(2)) = 5*(nC1)^2<br>
{{{8((n+1)(n))/2 = 5(n)^2}}}
{{{8n(n+1) = 10n^2}}}
{{{8n^2+8n = 10n^2}}}
{{{2n^2-8n = 0}}}
{{{2n(n-4) = 0}}}<br>
ANSWER: n=4<br>
CHECK:
8*5C3 = 8*5C2 = 8*10 = 80
5*(4C1)^2 = 5*16 = 80