The task is to generate the correct answer for a given math problem.

[Q]: Problem: the average of 5 quantities is 12 . the average of 3 of them is 4 . what is the average of remaining 2 numbers ?
[A]: 24


[Q]: Problem: if the cost price of 50 articles is equal to the selling price of 40 articles , then the gain or loss percent is ?
[A]: 25 %


[Q]: Problem: the average height of 30 girls out of a class of 40 is 160 cm . and that of the remaining girls is 156 cm . the average height of the whole class is :
[A]:
159 cms