Task: Question Answering
Input (English): Problem: if x : y is 1 : 5 and y : z is 5 : 7 then x : z is equal to 
Options: a ) 1 : 6 , b ) 1 : 5 , c ) 1 : 4 , d ) 1 : 7 , e ) 1 : 3
Output (English): d