Alex flips a fair coin 20 times. Bert spins a fair coin 21
times. Bert wins if he gets more heads than Alex, else Alex wins.
Note that Alex wins if there is a tie. What is the probability that
Bert wins?
On my TI83 calculator
sum(seq((binompdf(21,.5,x)*binomcdf(20,.5,x)),x,0,20)
gives .6223851943 (replace the first .5 with the appropriate probability if Bert really does get to spin.
So winning in a tie is better than getting an extra spin.
gotta like a 1 line solution
Jer

Posted by Jer
on 20040520 14:19:31 