13 2/5 - 11,2 : 9 1/3 = 12 1/5
1) 11,2 : 9 1/3 = 11 1/5 : 9 = 56/5 : 28/3 = 6/5
2) 13 2/5 - 6/5 = 67/5 - 6/5 = 61/5 = 12 1/5
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3,6 + 4,8(8 3/4 - 7 5/6) = 8
1) 8 3/4 - 7 5/6 = 1 + (3/4-5/6) =1+9/12-10/12=21/12-10/12= 11/12
2) 4,8*11/12 =4 8/10*11/12= 4 4/5* 11/12=24/5*11/12= 22/5=4,4
3) 3,6 + 4,4 = 8