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

Example Input: 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 ?
Example Output: 70

Example Input: Problem: during a car trip , maria stopped to rest after she traveled 1 / 2 of the total distance to her destination . she stopped again after she traveled 1 / 4 of the distance remaining between her first stop and her destination , and then she drove the remaining 135 miles to her detination . what was the total distance , in miles from maria ' s starting point to her destination ?
Example Output: 360

Example Input: Problem: the average marks of a class of 40 students is 44 and that of another class of 45 students is 70 . find the average marks of all the students ?
Example Output:
69.5