Answer: 60 books
Explanation:
One customer buys 1/4 of a book vendor's books , another buys 1/3 of his books ,and the third person buys 1/6 of his books.
The lowest common multiple of 4, 3 and 6 is 12
1/4 × 12 = 3
1/3 × 12 = 4
1/6 × 12 = 2
We add all together= 3+4+2= 9
So we've gotten our numerators as 9 and denominator as 12 which is 9/12 = 3/4
Since the total books bought is 3/4. The fraction of books left will be
1-3/4 = 1/4
The book vendor has 15 books left. So we divide 15 by 1/4.
= 15 ÷ 1/4
= 15 × 4
= 60