In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: a sells a bicycle to b and makes a profit of 25 % . b sells the same bicycle to c at a profit of 25 % . if the final s . p . of the bicycle was rs . 225 , find out the cost price of the bicycle for a . 
Options: a ) 237 , b ) 126 , c ) 971 , d ) 611 , e ) 144

A: e
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Q: Problem: at what rate of compound interest per annum will a sum of rs . 1200 become rs . 1348.32 in 2 years 
Options: a ) 3 % , b ) 4 % , c ) 5 % , d ) 6 % , e ) 7 %

A: d
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Q: Problem: of 440 surveyed students , 20 % of those who read book a also read book b and 25 % of those who read book b also read book a . if each student read at least one of the books , what is the difference between the number of students who read only book a and the number of students who read only book b ? 
Options: a ) 20 , b ) 25 , c ) 30 , d ) 35 , e ) 55

A:
e
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