2025 · Q45
The ratio of sum of two numbers to their difference is 5 : 1. What is the ratio of the sum of their squares to the difference of their squares?
Elementary MathematicsRatio and Proportion
- A13 : 5
- B25 : 1
- C9 : 4
- D16 : 1
Explanation
(a+b)/(a−b) = 5 gives a + b = 5a − 5b, so 4a = 6b and a:b = 3:2. Then (a²+b²)/(a²−b²) = (9+4)/(9−4) = 13/5, option (a).