In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[EX Q]: Problem: the average of the marks of 30 students in a class is 45 . if the marks of each student are doubled , find the new average ? 
Options: a ) 85 , b ) 77 , c ) 33 , d ) 90 , e ) 75
[EX A]: d

[EX Q]: Problem: patrick purchased 60 pencils and sold them at a loss equal to the selling price of 20 pencils . the cost of 60 pencils is how many times the selling price of 60 pencils ? 
Options: a ) 0.75 , b ) 0.8 , c ) 1 , d ) 1.33 , e ) 1.75
[EX A]: d

[EX Q]: Problem: a part - time employee whose hourly wage was decreased by 20 percent decided to increase the number of hours worked per week so that the employee ' s total income did not change . by what percent e should the number of hours worked be increased ? 
Options: a ) 12.5 % , b ) 20 % , c ) 25 % , d ) 50 % , e ) 100 %
[EX A]:
c