Task: Question Answering
Input (English): Problem: the sides of the triangle are in the ratio 5 : 6 : 7 and its perimeter is 720 cm . the length of the longest side is ? 
Options: ['a ) 150 cm', 'b ) 200 cm', 'c ) 162 cm', 'd ) 220 cm', 'e ) 280 cm']
Output (English): e