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: if xy > 0 , 1 / x + 1 / y = 4 , and 1 / xy = 6 , then ( x + y ) / 2 = ? 
Options: a ) 1 / 25 , b ) 1 / 6 , c ) 1 / 5 , d ) 1 / 3 , e ) 6

A: d
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Q: Problem: each child has 6 crayons and 12 apples . if there are 12 children , how many crayons are there in total ? 
Options: a ) 22 , b ) 65 , c ) 72 , d ) 78 , e ) 90

A: c
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Q: Problem: if a = { 17 , 27 , 31 , 53 , 61 } , what is the sum of mean and median of the numbers in a ? 
Options: a ) 69 , b ) 75 , c ) 82 , d ) 91 , e ) 56

A:
a
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