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'.

Problem: if the price of gasoline increases by 25 % and a driver intends to spend only 5 % more on gasoline , by how much percent should the driver reduce the quantity of gasoline that he buys ? 
Options: a ) 20 % , b ) 16 % , c ) 15 % , d ) 12 % , e ) 10 %
b

Problem: which number need to add to 7844213 to get a number exactly divisible by 549 ? 
Options: a ) 418 , b ) 148 , c ) 448 , d ) 248 , e ) 348
c

Problem: the average of 6 no . ' s is 3.95 . the average of 2 of them is 3.4 , while the average of theother 2 is 3.85 . what is the average of the remaining 2 no ' s ? 
Options: a ) 2.3 , b ) 2.5 , c ) 3.5 , d ) 3.6 , e ) 4.6

e