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: walking 7 / 6 of his usual rate , a boy reaches his school 3 min early . find his usual time to reach the school ? 
Options: a ) 21 , b ) 28 , c ) 99 , d ) 77 , e ) 66

A: a
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Q: Problem: a man invests rs . 3,000 at the rate of 5 % per annum . how much more should he invest at the rate of 8 % , so that he can earn a total of 6 % per annum ? 
Options: a ) rs . 1200 , b ) rs . 1300 , c ) rs . 1500 , d ) rs . 2000 , e ) none of these

A: c
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Q: Problem: a trader marked the selling price of an article at 12 % above the cost price . at the time of selling , he allows certain discount and suffers a loss of 1 % . he allowed a discount of : 
Options: a ) 10 % , b ) 10.5 % , c ) 11 % , d ) 12.5 % , e ) 9.8

A:
e
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