9 7/11 - х = 3 3/11
х = 9 7/11 - 3 3/11
х = 6 4/11
---------------
х + 2 1/13 = 10 2/13
х = 10 2/13 - 2 1/13
х = 8 1/13
----------------------------------------------------------
8 6/17 - х = 5 3/17
х = 8 6/17 - 5 3/17
х = 3 3/17
--------------------
х + 3 6/7 = 8 3/7
х = 8 3/7 - 3 6/7
х = 7 10/7 - 3 6/7
х = 4 4/7