I reall need some help with this question,
"Let A and B be events with P(A)=1/2, P(B)=1/3, and P(A and B)=1/4
Determine: P(A U B)
P(A U B) = P(A) + P(B) - P(A ∩ B) ....so we have
P (A U B) = [ 1/2 + 1/3 - 1/4 ] = [ 5/6 - 1/4 ] = [20 - 6] / 24 = 14/24 = 7/12
