4 2/7 : 6 + ( 3 2/9+1 5/6) • 1 5/13
1)4 2/7 : 6 = 5/7 2)3 2/9+1 5/6 = 5 1/18 3)5 1/18*1 5/13 = 7 4) 5/7+7 = 7 5/7