Question

If n(A) = 40, n(B) = 50 and n(AUB) =75.
Find a) n (An B)
b) n (A - B)
c) n (B-A)​

Answer 1

Answer:

n(A∩B) = 15

n (A - B) = 25

n (B-A) = 35

Step-by-step explanation:

Given:

n(A) = 40

n(B) = 50

n(AUB) =75

n(A∩B) = ?

☆ n(AUB) = n(A) + n(B) - n(A∩B)

75 = 40 + 50 - n(A∩B)

☆ n(A∩B) = 90 - 75 = 15

n(A∩B) = 15

☆ n (A - B) = n(A) - n(A∩B)

n (A - B) = 40 - 15 = 25

n (A - B) = 25

☆ n (B-A)​ = n(B) - n(A∩B)

n (B-A) = 50 - 15 = 35

n (B-A) = 35