Three boys, on an average, are 25 years old, and their age are in the ratio of 3 : 5 : 7. What is the age of youngest boy?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 15 years.
Average age of 3 boys = Total sum of age/Number of boys
Total age of all 3 boys = 25 × number of boys
Total age = 25 × 3 = 75
According to the question,
⇒ 3x + 5x + 7x = 75
⇒ 15x = 75
⇒ x = 5
Hence,
Age of the smallest boy = 3x = 3(5) = 15 years