Question

100% INSANE IMPOSSIBLE QUESTION!?!!

17 balls, each have a 40% chance of being red. What is the probability that more than 10 are red?

Answer 1

So since this is a binomial, do I find the mean and standard deviation standardize it to find z-score?

Answer 2

Nope. Let N be the number of balls which turn red.
Take into account the fact that there are not 17 but 18 possible values for N. See why?

Now the hint.
For which value of k do you have P(N >= k) = 1/2 ?