Q6
The average age of three boys is 15 years. If their ages are in ratio 3 : 5 : 7, the age of the youngest boy is
A.
21 years
B.
18 years
C.
15 years
D.
9 years
AnswerE.
12 years
Answer: Option D
Solution
Answer: Option D
Solution:
Sum of ages of three boys = 45 yearsNow, (3x + 5x + 7x) = 45
⇒ 15x = 45
⇒ x = 3
So, age of youngest boy = 3x
= 3 × 3
= 9 years