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'.

[Q]: Problem: a certain car traveled twice as many miles from town a to town b as it did from town b to town c . from town a to town b , the car averaged 20 miles per gallon , and from town b to town c , the car averaged 25 miles per gallon . what is the average miles per gallon that the car achieved on its trip from town a through town b to town c ? 
Options: a ) 20 , b ) 18 , c ) 21.4 , d ) 16 , e ) 10
[A]: c


[Q]: Problem: 3 times the first of 3 consecutive odd integers is 3 more than twice the third . the third integer is ? 
Options: a ) 15 , b ) 17 , c ) 19 , d ) 21 , e ) 26
[A]: a


[Q]: Problem: for the past n days , the average ( arithmetic mean ) daily production at a company was 50 units . if today ' s production of 90 units raises the average to 54 units per day , what is the value of n ? 
Options: a ) 30 , b ) 18 , c ) 10 , d ) 9 , e ) 7
[A]:
d