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: a trader mixes 80 kg of tea at 15 per kg with 20 kg of tea at cost price of 20 per kg . in order to earn a profit of 50 % , what should be the sale price of the mixed tea ? 
Options: a ) 23.75 , b ) 22 , c ) 20 , d ) 19.2 , e ) none of these
[EX A]: e

[EX Q]: Problem: if 40 % of a certain number is 160 , then what is 90 % of that number ? 
Options: a ) 270 , b ) 380 , c ) 260 , d ) 360 , e ) 290
[EX A]: d

[EX Q]: Problem: a sum of money at simple interest amounts to rs . 815 in 3 years and to rs . 884 in 4 years . the sum is : 
Options: a ) s . 608 , b ) s . 690 , c ) s . 698 , d ) s . 700 , e ) s . 760
[EX A]:
a