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: the average age of 15 students of a class is 15 years . out of these , the average age of 8 students is 14 years and that of the other 6 students is 16 years , the age of the 15 th student is 
Options: a ) 17 , b ) 12 , c ) 13 , d ) 14 , e ) 15

Answer: a


Question: Problem: in a group of ducks and cows , the total number of legs are 36 more than twice the number of heads . find the total number of cows . 
Options: a ) 12 , b ) 14 , c ) 16 , d ) 18 , e ) 20

Answer: d


Question: Problem: in a class of 40 students , 5 students did not borrow any books from the library , 15 students each borrowed 1 book , 10 students each borrowed 2 books , and the rest of the students each borrowed at least 3 books . if the average ( arithmetic mean ) number of books borrowed per student was 2 , what is the maximum number of books that any single student could have borrowed ? 
Options: a ) 3 , b ) 5 , c ) 8 , d ) 13 , e ) 18

Answer:
e