The average age of 66
3
2
% of the number of children in a group is 13 years. The average age of all the children in the group is 14.5 years. What is the average age (in years) of the remaining children?
- A16.5
- B15
- C13.5
- D17.5
Solution & Step-by-step Explanation
Let the total number of children in the group be 3 (since 66
3
2
%=
3
2
).
Number of children in the first group =
3
2
×3=2
Remaining number of children =3−2=1
The average age of the 2 children is 13 years, so their total age is:
Sum
1
=2×13=26 years
The average age of all 3 children is 14.5 years, so the overall total age is:
Total Sum=3×14.5=43.5 years
The age of the remaining 1 child is:
Age of remaining child=Total Sum−Sum
1
=43.5−26=17.5 years
Since there is only 1 remaining child, the average age of the remaining children is 17.5 years.
3
2
%=
3
2
).
Number of children in the first group =
3
2
×3=2
Remaining number of children =3−2=1
The average age of the 2 children is 13 years, so their total age is:
Sum
1
=2×13=26 years
The average age of all 3 children is 14.5 years, so the overall total age is:
Total Sum=3×14.5=43.5 years
The age of the remaining 1 child is:
Age of remaining child=Total Sum−Sum
1
=43.5−26=17.5 years
Since there is only 1 remaining child, the average age of the remaining children is 17.5 years.