9. The ages of a family of five sum to 80 . The two youngest are 6 and 8 . What was the sum of the ages of the family seven years ago?
A 35
B 36
C 45
D 46
E 66
SOLUTION
D

Seven years ago, the youngest child had not been born and so did not contribute to the sum of their ages. The sum of the four eldest members of the family is 74. Therefore, seven years ago, the sum of their ages was $74-28$, that is 46 .