Question

If E and F are events such that P(E) = ¼ P(F) = ½ and P (E and F) = 1/8 Find P(not E and not F)

• A. 1/4
• B. 1/2
• C. 3/8
• D. 1/16

Answer 1

Answer:

C. 3/8

P(E) = ¼ P(F) = ½ and P (E and F) = 1/8 P(not E and not F) = P(E' ∩ F') = P(E ∪ F)' = 1 - P(E ∪ F) = 1- [P(E) + P(F) - P(E ∩ F)] = 1 - [ 1/4 + 1/2 - 1/8] = 1 - 5/8 = 3/8