4/9=5/9-1/9
6/14=12/14-6/14
5/42=39/42-34/42
8/16=10/16-2/16
а 6/9-2/9=4/9
б 10/14-4/14=6/14
в 25/42-20/42=5/42
г 15/16-7/16=8/16
4/9=5/9-1/9
6/14=12/14-6/14
5/42=39/42-34/42
8/16=10/16-2/16
а 6/9-2/9=4/9
б 10/14-4/14=6/14
в 25/42-20/42=5/42
г 15/16-7/16=8/16