The average age of three boys is 15 years. If their ages are in the ratio 3:5:7 the average age of the young boy is ______ years?	Answers
A) 18
B) 8
C) 9
D) 19
E) 17
avg of three boys is 15 years given ratio of their ages are 3:5:7   let x be the age   (3x+5x+7x)/3 =15 implies x=3   then the age of the young boy is 3x3=9   ANSWER:9
<result>C</result>
The average age of three boys is 15 years. If their ages are in the ratio 3:5:7 the average age of the young boy is ______ years?