In a certain code language, '+' represents 'x', '-' represents '+', 'x' represents '÷' and '÷' represents '-'. What is the answer to the following question?
Some equations are solved on the basis of certain system. Find out the correct answer for unsolved equation on that basis: 4 x 5 x 8 = 584, 7 x 3 x 9 = 397, 9 x 7 x 3 = ?