In a community library, there are three sections: Fiction, Non-Fiction, and Children’s books. The average number of books in the Fiction and Non-Fiction sections is 1,275. The average number of books in the Non-Fiction and Children’s sections is 1,450. If the total number of books in all three sections is 3,900, find the number of books in the Non-Fiction section.
Show answer & explanation
Correct answer: B
Explanation
Given:
(F + N)/2 = 1275
(N + C)/2 = 1450
F + N + C = 3900
F + N = 2 × 1275 = 2550
N + C = 2 × 1450 = 2900
(F + N) + (N + C) = 2550 + 2900 = 5450
F + 2N + C = 5450
(F + N + C) + N = 5450
3900 + N = 5450
N = 1550