The average age of four children in a family is 12 years. If the spacing between their ages is 4 years, the age of the youngest child is ?
Choose the correct choice.
A) 6 years
B) 7 years
C) 8 years
D) 9 years
E) None
Answer   Let the age of youngest child be y.   so from question y + (y + 4) + (y + 8) + (y + 12) = 4 x 12   ⇒ 4y + 24= 48   ∴ y = 6 years   Correct Option: 6 years
<result>A</result>
The average age of four children in a family is 12 years. If the spacing between their ages is 4 years, the age of the youngest child is ?