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'.
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Question: Problem: what is the rate percent when the simple interest on rs . 800 amount to rs . 200 in 4 years ? 
Options: a ) 5 % , b ) 7 % , c ) 6.25 % , d ) 2 % , e ) 4 %

Answer: c


Question: Problem: of 600 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 ) 75

Answer: e


Question: Problem: one night a certain hotel rented 3 / 5 of its rooms , including 2 / 3 of their air conditioned rooms . if 3 / 5 of its rooms were air conditioned , what percent of the rooms that were not rented were air conditioned ? 
Options: a ) 50 % , b ) 55 % , c ) 60 % , d ) 65 % , e ) 70 %

Answer:
a