Solution Wanted!
b(k;n,1/2) = =
= $\sum^n_{k=1} \frac{{n \choose k}{n \ choose n-k}}{2^n2^n}$ = ${2n \choose n}/4^n$.
No success = = 1/e Exact one success = = 1/e
b(k;n,p) = = = b(n-k; n, 1-p)
Let p = = 5/16 E[X] = 16/5
= = 1
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