Problem 4 Find n(S intersect T) given that n(S) = 4, n(T) = 12, and
n(S union T) = 15.


Problem 10 Suppose that all of the 1000 first year students at a certain
college are enrolled in a math or an English course. Suppose that
400 are taking both math and English and 600 are taking English. How many
are taking a math course?