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'.

[EX Q]: Problem: the difference between simple and compound interest on rs . 1600 for one year at 10 % per annum reckoned half - yearly is ?
Options: a ) 8 , b ) 3 , c ) 9 , d ) 4 , e ) 2
[EX A]: d

[EX Q]: Problem: solve the quickfire maths brain teaser a s 25 % = ?
Options: a ) 30 % , b ) 40 % , c ) 50 % , d ) 19 % , e ) 29 %
[EX A]: c

[EX Q]: Problem: a man buy a book in rs 50 & sale it rs 100 . what is the rate of profit ? ? ?
Options: a ) 10 % , b ) 100 % , c ) 30 % , d ) 25 % , e ) 28 %
[EX A]:
b