For the expected value, it is the sum of x(P)x. And E(X)=mean. So you have to figure out the probabilities for each category first. 0 cups=.28, 1 cup=.36,2 cups=.24,3 cups=.12.
But from here I’m stumped. Do I use Sum(X-Mu)^2*P(X)
More interested in the process to calculate than the answer as we can practice our quizzes endlessly to practice for test, values change every time.