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: a question paper has 2 parts , a & b , each containing 8 questions . if a student has to choose 8 from part a & 4 from part b , in how many ways can he choose the questions ?
[A]: 70


[Q]: Problem: in a particular city there are 100 homes numbered from 1 , 23 , . . , 100 . the city was build by a builder from chennai . there was 4 to 5 shops in the town which was build by a builder from mumbai . the 2 nd builder can build in 1 ½ times as compared to time by 1 st builder . the 2 nd builder builds in 15 days , then how many 2 ' s are used by the builder from chennai in numbering the 100 homes ?
[A]:
20