Найдите значение 1/3-1/4;1/3-1/6;3/20+3/4;7/9-2/3;1/4+1/5.

1/3-1/4=4/12-3/12=1/121/3-1/6=2/6-1/6=1/63/20+3/4=3/20+15/20=18/20=9/107/9-2/3=7/9-6/9=1/91/4+1/5=5/20+4/20=9/20