2012 · Q22
A number consists of two digits whose sum is 8. If 18 is added to the number, the digits are reversed. The number is equal to:
Elementary MathematicsNumber System
- A26
- B35
- C53
- D62
Explanation
a+b = 8 and 9(b-a) = 18 give b-a = 2, so a = 3, b = 5; the number is 35.