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'.
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Question: Problem: if 3 x – 5 y = 5 and x / x + y = 5 / 7 , then what is the value of x – y ? 
Options: a ) 9 , b ) 6 , c ) 4 , d ) 3 , e ) none of these

Answer: d


Question: 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

Answer: a


Question: Problem: if x and y are integers such that | y + 3 | ≤ 3 and 2 y – 3 x + 6 = 0 , what is the least possible value t of the product xy ? 
Options: a ) - 12 , b ) - 3 , c ) 0 , d ) 2 , e ) none of the above

Answer:
c