(2 целых 5/7-1 целую 3/5): 1,3-1 целая 3/7 *0,25 /(2/5-7/18)*15

(2 5/7 -1 3/5):1,3 + 1 3/7· 0,25  /  (2/5 - 7/18) · 15 = 3
1)2 5/7 - 1 3/5 = 2 25/35 - 1 21 /35 = 1 4/35
2) 1 4/35 : 1 3/10=39/35: 13/10=39/35 · 10/13 =6/7
3)1 3/7 · 1/4=10/7 · 1/4 = 5/14
4) 2/5 - 7/18 =36/90 - 35/90 = 1/90
5) 1/90 · 15= 1/6
6)5/14 : 1/6 = 5/14 · 6/1 = 15/7= 2 1/7
7) 6/7 +2 1/7=2 7/7 = 3