Task: Question Answering
Input (English): Problem: if the ratio of s . i earned on certain amount on same rate is 4 : 5 . what is the ratio of time ? 
Options: a ) 1 : 2 , b ) 6 : 9 , c ) 4 : 5 , d ) 2 : 3 , e ) not possible to calculate
Output (English): c