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 age of a group of 10 persons was decreased by 3 years when one person , whose age was 42 years , was replaced by a new person . find the age of the new person ? 
Options: a ) 22 , b ) 18 , c ) 12 , d ) 88 , e ) 66

A: c
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Q: Problem: if x : y = 3 : 5 , find the value of ( 2 x + 4 y ) : ( 3 x – y ) 
Options: a ) 13 : 2 , b ) 11 : 2 , c ) 13 : 3 , d ) 13 : 4 , e ) 13 : 5

A: a
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Q: Problem: how many words , with or without meaning , can be formed using all letters of the word good using each letter exactly once ? 
Options: a ) 18 , b ) 20 , c ) 22 , d ) 23 , e ) 24

A:
e
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