(5 7/9-х)+2 3/4=3 5/12
5 7/9-х=3 5/12-2 3/4 решение
3 5/12-2 3/4=1 5/12-3/4=17/12-3/4=17/12-9/12=8/12=2/3
5 7/9-х=2/3
х=5 7/9-2/3 решение 5 7/9-2/3=52/9-2/3=52/9-6/9=46/9=5 1/9
х=5 1/9
(5 7/9-х)+2 3/4=3 5/12
5 7/9-х=3 5/12-2 3/4 решение
3 5/12-2 3/4=1 5/12-3/4=17/12-3/4=17/12-9/12=8/12=2/3
5 7/9-х=2/3
х=5 7/9-2/3 решение 5 7/9-2/3=52/9-2/3=52/9-6/9=46/9=5 1/9
х=5 1/9