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: sandy buys an old scooter for $ 800 and spends $ 200 on its repairs . if sandy sells the scooter for $ 1400 , what is the gain percent ? 
Options: a ) 20 % , b ) 30 % , c ) 40 % , d ) 50 % , e ) 60 %

SOLUTION: c

PROBLEM: Problem: a can complete a certain job in 19 days . b is 90 % more efficient than a . in how many days can b complete the same job ? 
Options: a ) 6 , b ) 6.25 , c ) 7 , d ) 7.5 , e ) 10

SOLUTION: e

PROBLEM: Problem: the water level in a reservoir has been dropping at the rate of 12 inches per day . exactly 5 days ago , the water level was at w inches . what will be the water level exactly 4 days from now if the rate at which the level is dropping remains the same ? 
Options: a ) w − 108 , b ) w − 56 , c ) w − 14 , d ) w + 14 , e ) w + 126

SOLUTION:
a