Question

The natural number A is a multiple of 6. When the sum of all the factors of A is 39, find the value of A.

Answer 1

A = 18

Explanation:

A is a multiple of 6, that is

A : 6, 12, 18, 24, 30, .......

Listing the factors gives

6 : 1, 2, 3, 6 → sum = 12

12 : 1, 2, 3, 4, 6, 12 → sum = 28

18 : 1, 2, 3, 6, 9, 18 → sum = 39

Thus A = 18