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: the present population of a town is 200 . population increase rate is 10 % p . a . find the population of town after 1 years ? 
Options: a ) 100 , b ) 120 , c ) 200 , d ) 220 , e ) 250

Answer: d


Question: Problem: a man has $ 10,000 to invest . he invests $ 4000 at 5 % and $ 3500 at 4 % . in order to have a yearly income of $ 500 , he must invest the remainder at : 
Options: a ) 4.6 % , b ) 3.6 % , c ) 6.4 % , d ) 7.8 % , e ) 8.9 %

Answer: c


Question: Problem: john and david can finish a job together in 6 hours . if john can do the job by himself in 8 hours , what percent of the job does david do ? 
Options: a ) 35 % , b ) 45 % , c ) 25 % , d ) 30 % , e ) 20 %

Answer:
c