Question 348023
this is a binomial problem


a picked out grape is green (p(G) = .22) or not green (p(N) = .78)


Charlie must pick out 3 or more green grapes to eat one


you need to sum the first 3 terms of the expansion (p(G) + p(N))^5


5C5{[p(G)]^5} + 5C4{[p(G)]^4}[p(N)] + 5C3{[p(G)]^3}{[p(N)]^2}