TASK DEFINITION: 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'.
PROBLEM: 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

SOLUTION: e

PROBLEM: Problem: if a lends rs . 3500 to b at 10 % per annum and b lends the same sum to c at 12 % per annum then the gain of b in a period of 3 years is ? 
Options: a ) 200 , b ) 210 , c ) 220 , d ) 225 , e ) 230

SOLUTION: b

PROBLEM: Problem: in what time a sum of money double itself at 2 % per annum simple interest ? 
Options: a ) 60 % , b ) 58 % , c ) 55 % , d ) 40 % , e ) 50 %

SOLUTION:
e