Task: Question Answering
Input (English): 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 10 miles per gallon , and from town b to town c , the car averaged 18 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 ) 13 , b ) 13.5 , c ) 14 , d ) 14.5 , e ) 15
Output (English): d