In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: john found that the average of 15 numbers is 40 . if 12 is added to each number then the mean of number is ? 
Options: a ) 52 , b ) 45 , c ) 65 , d ) 78 , e ) 64

A: a
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Q: Problem: the total price of a basic computer and printer are $ 2,500 . if the same printer had been purchased with an enhanced computer whose price was $ 500 more than the price of the basic computer , then the price of the printer would have been 2 / 5 of that total . what was the price of the basic computer ? 
Options: a ) 1300 , b ) 1600 , c ) 1750 , d ) 1900 , e ) 2000

A: a
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Q: Problem: a car traveled 35 % of the way from town x to town y at an average speed of 35 mph . the car traveled at an average speed of v mph for the remaining part of the trip . the average speed for the entire trip was 50 mph . what is v in mph ? 
Options: a ) 45 , b ) 65 , c ) 55 , d ) 75 , e ) 85

A:
b
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