12 - х = 1 1/9
х = 12 - 1 1/9
х = 11 9/9 - 1 1/9
х = 10 8/9
5 8/9 + х = 7 1/18
х = 7 1/18 - 5 8/9
х = 7 1/18 - 5 16/18
х = 6 19/18 - 5 16/18
х = 1 3/18
х = 1 1/6
1) 6 3/4 - 2 19/20 = 6 15/20 - 2 19/20 = 5 35/20 - 2 19/20 = 3 16/20 = 3 4/5 во втором магазине
2) 6 3/4 + 1 9/20 = 6 15/20 + 1 9/20 = 7 24/20 = 7 6/5 = 8 1/5 в третьем магазине
3) 3 4/5 + 8 1/5 + 6 3/4 = 3 16/20 + 8 4/20 + 6 15/20 = 17 35/20 = 17 7/4 = 18 3/4 во всех трех магазинах
5 4/5 - 3 3/4 + 8 7/15 - 9 5/12 = 5 48/60 - 3 45/60 + 8 28/60 - 9 25/60 = 1 6/60 = 1 1/10 = 1,1
18 11/12 - 4 5/9 - 5 1/8 + 4 1/4 = 18 66/72 - 4 40/72 - 5 9/72 + 4 18/72 = 13 35/72
4 3/4 - 3,75) + (9 5/6 - 3 17/18) = 6 8/9
1) 4 3/4 - 3,75 = 4 3/4 - 3 75/100 = 4 75/100 - 3 75/100 = 1
2) 9 5/6 - 3 17/18 = 9 15/18 - 3 17/18 = 8 33/18 - 3 17/18 = 5 16/18 = 5 8/9
3) 1 + 5 8/9 = 9/9 + 5 8/9 = 5 17/9 = 6 8/9