Question

Se n(AUB)=30, n(A)=15, n(B)=20, Determine, n (A ∩ B): * (A)4 (B)6 (C)3 (D)7 (E)5 E de marca x

Answer 1

n(AUB) = n(A) + n(B) - n(A∩B)

30 = 15 + 20 - n(A∩B)

n(A∩B) = 15 + 20 - 30

n(A∩B) = 5

R: e)5