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: the average ( arithmetic mean ) of 4 positive integers is 50 . if the average of 2 of these integers is 35 , what is the greatest possible value that one of the other 2 integers can have ? 
Options: a ) 55 , b ) 65 , c ) 100 , d ) 109 , e ) 129

A: e
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Q: Problem: marcella has 27 pairs of shoes . if she loses 9 individual shoes , what is the greatest number of matching pairs she could have left ? 
Options: a ) 22 , b ) 20 , c ) 19 , d ) 16 , e ) 15

A: a
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Q: Problem: find the missing value : ? - 1936248 = 1635773 
Options: a ) 3572021 , b ) 3570221 , c ) 3572012 , d ) 3752012 , e ) none of them

A:
a
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