Posted by Andrew on .
for n repeated independent trials, with constant probability of success p for all trials, find the probability of exactly x succes n=5,p=1/3, x=4

math 
joanna,
If there are only two possible outcomes from each trial then it's a binomial and by using the formula nCx p^x(1p)^(nx) we get; 5C4(1/3)^4(2/3)^1=0.04115