The task is to generate the correct answer for a given math problem.
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Question: Problem: a train running at the speed of 72 km / hr crosses a pole in 9 seconds . find the length of the train .

Answer: 180 meter

Question: Problem: you collect baseball cards . suppose you start out with 15 . maria takes half of one more than the number of baseball cards you have . since you ' re nice , you give peter 1 baseball card . since his father makes baseball cards , paul decides to triple your baseball cards . how many baseball cards do you have at the end ?

Answer: 18

Question: Problem: the grade point average of the entire class is 90 . if the average of one third of the class is 96 , what is the average of the rest ?

Answer:
87