Assume any pager selected from the box is done randomly, and hence selections are independent from each other. The probability of a selected pager being defective is 0.25. Let X be the random variable for the number of defective pagers.
A) Determine the probability of selecting exactly 2 defective pagers.
B) Determine the probability of selecting at least 5 defective pagers.
I tried P(X = 2) = 0.25^2, but I'm not sure if that's the correct approach for A)