х - 4 3/7 - 3 5/14=х - 4 6/14 - 3 5/14=х - 7 11/14
(х - 9 3/7)+5 5/21 - 6 2/3=х - 9 9/21+5 5/21 - 6 14/21=х - 10 18/21=х - 10 6/7
х - 4 3/7 - 3 5/14=х - 4 6/14 - 3 5/14=х - 7 11/14
(х - 9 3/7)+5 5/21 - 6 2/3=х - 9 9/21+5 5/21 - 6 14/21=х - 10 18/21=х - 10 6/7