Final answer:
To find n(B) in the given problem, we use the formula n(A ∪ B) = n(A) + n(B) - n(A ∩ B). Plugging in the given values, we can solve for n(B) and find that it is equal to 100.
Step-by-step explanation:
In this problem, we are given that n(A) = 102, n(A ∪ B) = 155, and n(A ∩ B) = 47. We are asked to find n(B).
To find n(B), we can use the formula n(A ∪ B) = n(A) + n(B) - n(A ∩ B).
Plugging in the given values, we have 155 = 102 + n(B) - 47.
Solving for n(B), we get n(B) = 155 - 102 + 47 = 100.