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: running at the same constant rate , 6 identical machines can produce a total of 270 bottles per minute . at this rate , how many bottles could 8 such machines produce in 4 minutes ? 
Options: a ) 648 , b ) 1800 , c ) 2700 , d ) 1440 , e ) none of these
[EX A]: d

[EX Q]: Problem: the true discount on a bill of rs . 2460 is rs . 360 . what is the banker ' s discount ? 
Options: a ) rs . 432 , b ) rs . 422 , c ) rs . 412 , d ) rs . 442 , e ) none of these
[EX A]: b

[EX Q]: Problem: if the given two numbers are respectively 7 % and 28 % of a third number , then what percentage is the first of the second ? 
Options: a ) 20 % , b ) 25 % , c ) 18 % , d ) 30 % , e ) none of these
[EX A]:
b