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: company x provides bottled water to its employees in 5 liter bottles , $ 2 each . at least how many 5 l bottles must company x buy monthly , so that new contract with $ 100 fixed monthly rate and $ 1 for 10 l bottle each paid off ? ( assume that no other costs apply ) 
Options: a ) 121 , b ) 125 , c ) 132 , d ) 134 , e ) 138

Answer: d


Question: 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

Answer: e


Question: Problem: the total age of a and b is 15 years more than the total age of b and c . c is how many years younger than a ? 
Options: a ) 12 , b ) 15 , c ) c is elder than a , d ) data inadequate , e ) none

Answer:
b