4целых 1/6*0,6+6 целых 2/5: 1 целую 1/7-6/7

4 1/6 * 0,6 + 6 2/5 : 1 1/7 - 6/7 = 7 17/70
1) 4 1/6 * 0,6 = 25/6 * 6/10 = 25/10 = 2,5
2) 6 2/5 : 1 1/7 = 32/5 : 8/7 = 32/5 * 7/8 = 28/5 = 5,6
3) 2,5 + 5,6 = 8,1
4) 8,1 - 6/7 = 8 1/10 - 6/7 = 8 7/70 - 60/70 = 7 77/70 - 60/70 = 7 17/70