Task: Question Answering
Input (English): Problem: exactly 3 / 7 of the people in the room are under the age of 21 , and exactly 5 / 14 of the people in the room are over the age of 65 . if the total number of the people in the room is greater than 50 and less than 100 , how many people in the room are under the age of 21 ? 
Options: a ) 21 , b ) 35 , c ) 39 , d ) 42 , e ) 65
Output (English): d