1) To prove P(E U F) >= 0.8, first express E U F as the union of 2 disjoint events (hint: consider set difference between F and E). Then use theorem 1 from page 404.
2) To prove P(EF) >= 0.4, use inclusion-exclusion principle, then use the fact that P(E U F) <= 1.
--Asuleime 02:17, 9 October 2008 (UTC)
There is an example in the book just like this one if you look at problem 11. The solution to 11 is written in the back of the book.__
