Выполните вычитание: 7/10-1/2, 13/20-3/8, 13/14-5/42, 3ц.1/6-2ц.1/12, 5ц.1/14-3ц.2/7.

7/10-1/2=7/10 - 5/10=2/10
13/20-3/8=26/40-15/40=11/40
13/14-5/42=39/42-5/42=34/42=17/21
3ц.1/6-2ц.1/12= 3ц 2/12-2ц 1/12=1ц 1/12
5ц.1/14-3ц.2/7.= 4ц 15/14 - 3ц 4/14=1ц. 11/14