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: what profit percent is made by selling an article at a certain price , if by selling at 4 / 5 rd of that price , there would be a loss of 20 % ? 
Options: a ) 0 % , b ) 29 % , c ) 70 % , d ) 27 % , e ) 28 %

A: a
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Q: Problem: a 6 litre sol is 30 % alcohol . how many litres of pure alcohol must be added to produce a sol that is 50 % alcohol ? 
Options: a ) a . 0.6 , b ) b . 1 , c ) c . 2.1 , d ) d . 3 , e ) e . 2.4

A: e
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Q: Problem: find the principal which yields a simple interest of rs . 20 and compound interest of rs . 25 in two years , at the same percent rate per annum ? 
Options: a ) s . 40 , b ) s . 48 , c ) s . 49 , d ) s . 20 , e ) s . 60

A:
a
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