Question

Let abc be a three digit number. Then abc + bca + cab is not divisible by ______.

Options

• a + b + c

• 3

• 37

• 9

Answer 1

Let abc be a three digit number. Then abc + bca + cab is not divisible by 9.

Explanation:

We know that, the sum of three-digit numbers taken in cyclic order can be written as 111(a + b + c).

i.e. abc + bca + cab = 3 × 37 × (a + b + c)

Hence, the sum is divisible by 3, 37 and (a + b + c) but not divisible by 9.