1) 2 целых 2/5 - (1/4+7/10)

2) 9 целых - (1 целая 5/8+3/20)

3) 3 целых - (1/6+2/3)

4) 4 целых 5/6 - (2 целых 3/8+7/12)

5) 7 целых - (2 целых 3/4 + 7/12)

6) 6 целых 1/4 - (3 целых 2/5+3/8

1) 2 2/5 - (1/4+7/10) = 2 2/5 - (5/20+14/20) = 2 2/5+19/20=2 8/20+19/20=2 27/20=3 7/20

2) 9 - (1 5/8+3/20) = 9 - (1 25/40+6/40) = 9-1 31/40=8-31/40=7 9/40

3) 3 - (1/6+2/3) = 3 - (1/6+4/6) = 3-5/6=2 1/6

4) 4 5/6 - (2 3/8+7/12) = 4 5/6 - (2 9/24+14/24) = 4 20/24-2 23/24=2-3/24=2-1/8=1 7/8

5) 7 - (2 3/4 + 7/12) = 7 - (2 9/12+7/12) = 7-2 16/12=7-2 4/3=7-3 1/3=4-1/3=3 2/3

6) 6 1/4 - (3 2/5+3/8) = 6 1/4 - (3 16/40+15/40) = 6 10/40+3 31/40=9 41/40=10 1/40