The sum of digits of a 2-digit number is 12. When the digits are reversed, the number becomes greater by eighteen. What is the difference between the digits in the number?

  1. A. 1
  2. B. 2
  3. C. 3
  4. D. 4

Correct Answer: B. 2

Explanation

Let the number be 10x + y. We have x + y = 12 and (10y + x) - (10x + y) = 18, which simplifies to 9(y - x) = 18, so y - x = 2. The difference is 2.

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