Question

Number 136 is added to 5B7 and the sum obtained is 7A3, where A and B are integers. It is given that 7A3 is exactly divisible by 3. The only possible value of B is
1. 2
2. 5
3. 7
4. 8

Answer 1

Correct Answer - Option 4 : 8

Concept:

The divisibility rule of 3 states that a number is completely divisible by 3 if the sum of its digit is divisible by 3 or multiple of 3.

Calculation:

⇒ 7 + A + 3 = 10 + A  (Possible value of A is 2, 5, 8)

⇒ 136 + 5B7 = 7A3    (Possible value of B is 6, 7, 8, 9)

⇒ For A = 2, B = 8

⇒ 7 + 2 + 3 = 12, (Which is divisible by 3 or multiple of 3)

⇒ The value of B = 8

∴ The required result will be 8.