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: what is the ratio of 3 / 7 to the product 2 * ( 7 / 3 ) ? 
Options: a ) 3 : 7 , b ) 9 : 98 , c ) 3 : 21 , d ) 1 : 7 , e ) 3 : 49

A: b
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Q: Problem: the age of somu is one - third his father ' s . 10 years back he was one - fifth of his father ' s age . what is his persent age ? 
Options: a ) 11 , b ) 13 , c ) 14 , d ) 12 , e ) 20

A: e
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Q: Problem: a group of students decided to collect as many paise from each member of group as is the number of members . if the total collection amounts to rs . 51.84 , the number of the member is the group is : 
Options: a ) 57 , b ) 67 , c ) 72 , d ) 87 , e ) 97

A:
c
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