Question
The average number of books read by 40 Indian students
in a year is 30. If the books read by their librarian are included, the average increases by 2 books. Find the number of books read by the librarian.Solution
ATQ, Total books read by the students excluding librarian = 40 × 30 = 1200 Let the books read by the librarian be ‘b’. According to the question, (1200 + b) / (40 + 1) = 30 + 2 1200 + b = 41 × 32 1200 + b = 1312 b = 1312 – 1200 b = 112. So, the librarian read 112 books.
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