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

[EX Q]: Problem: if p / q = 3 / 11 , then 2 p + q = ?
[EX A]: 17

[EX Q]: Problem: two trains of equal length , running with the speeds of 60 and 90 kmph , take 50 seconds to cross each other while they are running in the same direction . what time will they take to cross each other if they are running in opposite directions ?
[EX A]: 6.6

[EX Q]: Problem: the average mark of the students of a class in a particular exam is 80 . if 5 students whose average mark in that exam is 60 are excluded , the average mark of the remaining will be 90 . find the number of students who wrote the exam .
[EX A]:
15