The present ages of three persons in proportions 3 : 7 : 5. Eight years ago, the sum of their ages was 51. Find their present ages (in years).  Answers.
A) 8, 20, 28  B) 16, 28, 36  C) 15,35,25  D) 18, 24, 32  E) None of these
Explanation:   Let their present ages be 3x, 7x and 5x years respectively.   Then, (3x - 8) + (7x - 8) + (5x - 8) = 51   15x = 75   x = 5   Their present ages are 3x = 15 years, 7x = 35 years and 5x = 25 years respectively.   Answer: 15,35,25
<result>C</result>
The present ages of three persons in proportions 3 : 7 : 5. Eight years ago, the sum of their ages was 51. Find their present ages (in years).