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: i bought two books ; for rs . 600 . i sold one at a loss of 15 % and other at a gain of 19 % and then i found each book was sold at the same price . find the cost of the book sold at a loss ? 
Options: a ) 197 , b ) 280 , c ) 189 , d ) 278 , e ) 350

SOLUTION: e

PROBLEM: Problem: if 28 % of a number exceeds 18 % of it by 7.2 , then find the number ? 
Options: a ) 50 , b ) 34 , c ) 55 , d ) 60 , e ) 90

SOLUTION: e

PROBLEM: Problem: at what rate percent per annum will a sum of money double in 9 years . 
Options: a ) 12.5 % , b ) 13.5 % , c ) 11.5 % , d ) 11.1 % , e ) 21.5 %

SOLUTION:
d