Task: Question Answering
Input (English): Problem: the average ( arithmetic mean ) of the 5 positive integers k , m , r , s , and t is 12 , and k < m < r < s < t . if t is 20 , what is the greatest possible value of the median of the 5 integers ? 
Options: a ) 16 , b ) 18 , c ) 19 , d ) 20 , e ) 22
Output (English): d