Problem: if 50 % of ( x - y ) = 30 % of ( x + y ) then what percent of x is y ?
Rationale: "50 % of ( x - y ) = 30 % of ( x + y ) ( 50 / 100 ) ( x - y ) = ( 30 / 100 ) ( x + y ) 5 ( x - y ) = 3 ( x + y ) 2 x = 8 y x = 4 y therefore required percentage = ( ( y / x ) x 100 ) % = ( ( y / 4 y ) x 100 ) = 25 % answer is e ."
annotated_formula: multiply(divide(subtract(50, 30), add(50, 30)), const_100)