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: a sum of money at simple interest amounts to $ 815 in 3 years and to $ 854 in 4 years . the sum is :
Options: a ) $ 153 , b ) $ 698 , c ) $ 398 , d ) $ 549 , e ) $ 675

Answer: b

Question: Problem: a sum of money at simple interest amounts to rs . 415 in 2 years and to rs . 514 in 4 years . the sum is ?
Options: a ) rs . 316 , b ) rs . 251 , c ) rs . 154 , d ) rs . 294 , e ) rs . 200

Answer: a

Question: Problem: in a certain village , 200 litres of water are required per household per month . at this rate , if there are 5 households in the village , how long ( in months ) will 2000 litres of water last ?
Options: a ) 9 , b ) 5 , c ) 6 , d ) 2 , e ) 4

Answer:
d