4 5\9 + 13\18 - ( 1 1\3 - 7\18)
4 5/9+13/18-(1 1/3-7/18)=4 1/3 1) 1 1/3-7/18=4/3-7/18=24/18-7/18=17/18 2) 4 5/9+13/18=41/9+13/18=82/18+13/18=95/18 3) 95/18=17/18=78/18=4 6/18=4 1/3