По деяньям, пожалуйста927

1. 5/7(21/20 - 7/30)+ 16/21: 8/7=1 1/4
а. 21/20-7/30=49/60
б. 5/7 49/60=7/12
в. 16/21: 8/7=2/3
г. 7/12+2/3=15/12= 1 3/12= 1 1/4

2.4/45:(12/25-4/15)+15/164/15=2/3
а. (12/25-4/15)=16/75
б. 4/45:16/75=15/36=5/12
в. 15/164/15=1/4
г. 5/12+1/4=8/12=2/3

3. 2: 2 2/3+ 1 4/5 3 1/3 - 2 5/6= 3 11/12
а. 2 : 2 2/3= 6/3:8/3=3/4
б. 1 4/5 3 1/3= 9/5 10/3=6
в. 3/4+6=6 3/4
г. 6 3/4 - 2 5/6= 4 (3/4-5/6)= 3 11/12

4. 3 : 3 3/4 + 2 2/5 2 1/2 - 3 5/6=2 29/30
а. 3 :3 3/4= 9/3 : 15/4=36/45=4/5
б. 2 2/5 2 1/2=12/5 5/2=6
в. 4/5 + 6 =6 4/5
г. 6 4/5 - 3 5/6 = 3 (4/5-5/6)= 2 29/30