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: a milk man has 15 liters of milk . if he mixes 5 liters of water , which is freely available , in 20 liters of pure milk . if the cost of pure milk is rs . 18 per liter , then the profit of the milkman , when he sells all the mixture at cost price is : 
Options: a ) 20 % , b ) 25 % , c ) 33.33 % , d ) 18 % , e ) none of these
a

Problem: the cost price of 16 articles is the same as the selling price of 12 articles . find the loss / profit percentages . 
Options: a ) 30 % , b ) 32.50 % , c ) 33 1 / 3 % , d ) 40 % , e ) 50 %
c

Problem: david ' s bank ' s saving amount is decreased 10 % due to loan payment and current balance is rs . 90000 . find the actual balance before deduction ? 
Options: a ) 8000 , b ) 8500 , c ) 9000 , d ) 9500 , e ) 100000

e