Пошаговое объяснение:
1) 3-1 7/20=2 20/20-1 7/20=1 13/20
1 13/20:9/25=33/20*25/9=55/12=4 7/12
5-4 7/12=4 12/12-4 7/12=5/12
5/12+1/8=10/24+3/24=13/24
2) 2 -1 23/35=1 35/35-1 23/35=12/35
12/35:9/25=12/35*25/9=20/21
5/6+20/21=35/42+40/42=75/42=1 33/42=1 11/14
1 11/14-1 2/7=1 11/14-1 4/14=7/14=1/2
Пошаговое объяснение:
1) 3-1 7/20=2 20/20-1 7/20=1 13/20
1 13/20:9/25=33/20*25/9=55/12=4 7/12
5-4 7/12=4 12/12-4 7/12=5/12
5/12+1/8=10/24+3/24=13/24
2) 2 -1 23/35=1 35/35-1 23/35=12/35
12/35:9/25=12/35*25/9=20/21
5/6+20/21=35/42+40/42=75/42=1 33/42=1 11/14
1 11/14-1 2/7=1 11/14-1 4/14=7/14=1/2