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

Q: 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 ?

A: 18
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Q: Problem: company x provides bottled water to its employees in 10 liter bottles , $ 2 each . at least how many 10 l bottles must company x buy monthly , so that new contract with $ 50 fixed monthly rate and $ 1 for 50 l bottle each paid off ? ( assume that no other costs apply )

A: 28
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Q: Problem: calculate the average of all the numbers between 10 and 86 which are divisible by 9 .

A:
49.5
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