Task: Question Answering
Input (English): Problem: some of 45 % - intensity red paint is replaced with 25 % solution of red paint such that the new paint intensity is 40 % . what fraction of the original paint was replaced ? 
Options: a ) 2 / 5 , b ) 1 / 4 , c ) 1 / 5 , d ) 1 / 7 , e ) 2 / 3
Output (English): b