4 2/5 -2/5-3/7= 4-3/7=3 7/7 -3/7=3 4/7
(8 3/4- 7 2/9)+2,25-27/9)=(35/4- 65/9)-0,75=315/36-260/36-0,75=55/36-3/4=55/36-27/36=28/36=7/9
3,15-2,15+2/3=1 2/3( одна целая 2/3)
5/12-1/12-2/3=1/3-2/3=-1/3
4 5/8 - (2 3/8 + 1/4)=4 5/8- 2 3/8 -1/4=2
-8 14/15 -1/3+4/15=-8 2/3-1/3=8 1/3
(7 11/13 -3,2)-(2 5/18 +1,8)= 37/13+ 41/18=666/234 +533/234=113/234