Let X denote the random variable that counts the number of tosses required to get r heads with a
coin whose chance of heads b. Show that P(X=n)=(n1r1)pr(1p)nr,nr..
Let X denote the random variable that counts the number of tosses req.pdf
1. Let X denote the random variable that counts the number of tosses required to get r heads with a
coin whose chance of heads b. Show that P(X=n)=(n1r1)pr(1p)nr,nr.