Выполните действие 4/7+5/6, 5/12+2/15, 9/20-5/12, 5/9-3/8

4/7 + 5/6= 24/42 + 35/42= 59/42= 1 17/42

5/12 + 2/15= 25/60 + 8/60= 33/60= 11/20

9/20 - 5/12= 27/60 - 25/60= 2/60= 1/30

5/9 - 3/8= 40/72 - 27/72= 13/72