2021 · Q26
If three positive numbers are in the ratio 2 : 3 : 5 and the sum of their squares is 1368, then what is sum of the numbers ?
Elementary MathematicsRatio and Proportion
- A30
- B45
- C60
- D75
Explanation
Write the numbers as 2k, 3k, 5k with k > 0. The sum of squares is 4k² + 9k² + 25k² = 38k² = 1368, so k² = 36 and k = 6. The numbers are 12, 18, 30, whose sum is 60. This is option (c).