The sum of the ages of three friends is 84. Four years ago, their ages were in the ratio 3:4:5. What is the current age of the oldest friend?
Show answer & explanation
Correct answer: B
Explanation
Sum of current ages of the three friends = 84 years
Sum of their ages 4 years ago = 84 − (3 × 4) = 84 − 12 = 72 years
Ratio of their ages 4 years ago = 3 : 4 : 5
Sum of ratio units = 3 + 4 + 5 = 12 units
Value of 1 unit = 72 / 12 = 6 years
Age of the oldest friend 4 years ago = 5 × 6 = 30 years
Current age of the oldest friend = 30 + 4 = 34 years
Therefore, the correct option is (B).