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 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: radha bought a watch for rs . 144 and got a percentage of profit equal to the cost price of the watch . what is the cost price of the watch ? 
Options: a ) rs . 72 , b ) rs . 78 , c ) rs . 80 , d ) rs . 90 , e ) rs . 92
[EX A]: d

[EX Q]: Problem: after decreasing 90 % in the price of an article costs rs . 320 . find the actual cost of an article ? 
Options: a ) 2777 , b ) 2987 , c ) 3200 , d ) 9977 , e ) 1671
[EX A]:
c