The task is to generate the correct answer for a given math problem.
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Question: Problem: a man purchased earphone on friday . but he forgot how much it cost . the data he have are mean expenditure of all 7 days is 500 . expenditure on mon , tue , wed , thurs , sat , sun are 450600 , 400500 , 550300 . on friday he purchased 3 things one earphone , one pen and one notebook . pen cost 30 and notebook cost 50 . then what is cost of earphone ?

Answer: 620


Question: Problem: line q has the equation 5 y – 3 x = 30 . if line s is perpendicular to q , has an integer for its y - intercept , and intersects q in the second quadrant , then how many possible line s ’ s exist ? ( note : intersections on one of the axes do not count . )

Answer: 22


Question: Problem: if q is a positive integer and q ^ 2 is divisible by 12 , then the largest positive integer that must divide q ^ 3 is

Answer:
6 ^ 3