Question 430324
 You play a game where you are to guess under which of 4 cups a coin has been placed. How many times would you expect to guess correctly in 20 plays of the game? Note that the coin is moved after each play.

-----
Binomial Problem with n = 20 and p = 1/4.
----------------
E(x) = np
E(x) = 20(1/4)
E(x) = 5
===========
Cheers,
Stan H.
===========