1. = 2 8/56+4 7/56= 6 15/56
2. =12 21/36+3 32/36-4 27/36= 11 26/36=11 13/18
3. =19/19-9/19=10/19
4. =4 11/11-4/11=4 7/11
5. =2 9/12-1 7/12=1 2/12 = 1 1/6
6. =7 2/8-4 5/8=6 10/8-4 5/8=2 5/8
3х-3=12*5/4
3х-3=15
3х=18
х=6
Вот ответ на твой вопрос 489 800
1-(1/2) = (2-1)/2 = 1/2
1-(1/3) = (3-1)/3 = 2/3
1-(3/4) = (4-3)/4 = 1/4
1-(11/20) = (20-11)/20 = 9/20
1-(2/5) = (5-2)/5 = 3/5
1-(3/10) = (10-3)/10 = 7/10
1-(7/9) = (9-7)/9 = 2/9
1-(14/25) = (25-14)/25=11/25