The average age of three boys is 20 years and their ages are in the proportion 2 : 3 : 5. The age of the youngest boy is:
Select the correct option:
A) 21 years
B) 18 years
C) 15 years
D) 9 years
E) None of these
Total age of 3 boys = (20 Ã— 3) years = 60 years. Ratio of their ages = 2 : 3 : 3.   Age of the youngest = (60 Ã— 3â„10) years = 18 years.   Answer 18 years
<result>B</result>
The average age of three boys is 20 years and their ages are in the proportion 2 : 3 : 5. The age of the youngest boy is: