21:3/4=28
17:5/2=6,8
63:7/10=90
31:0,8=38,75
1) 21:3/4 = 21*4/3 = 84:3 = 28
2) 17:5/2 = 17*2/5 = 34:5 = 6,8
или 2/5 = 17
17:2/5 = 17*5/2 = 85:2 = 42,5
3) 63:7/10 = 63*10/7 = 630:7 = 90
4) 31:0,8 = 38,75
21:3/4=28
17:5/2=6,8
63:7/10=90
31:0,8=38,75
1) 21:3/4 = 21*4/3 = 84:3 = 28
2) 17:5/2 = 17*2/5 = 34:5 = 6,8
или 2/5 = 17
17:2/5 = 17*5/2 = 85:2 = 42,5
3) 63:7/10 = 63*10/7 = 630:7 = 90
4) 31:0,8 = 38,75