Discuss Forum

1. If the two digit integers M and N are positive and have the same digits, but in reverse order, which of the following CANNOT be the sum of M and N?

  • A. 181
  • B. 181
  • C. 181
  • D. 181

Answer: Option A

Explanation:

Let the first digit be xy, then the second digit would be yx.

xy = 10x + y
yx = 10y + x

sum = 11 (x+y)

so the sum has to be multiple of 11. 181 is not. so 181 be the answer


Post your comments here:

Name:
Mobile:
Email:(Optional)

» Your comments will be displayed only after manual approval.