(15 5/12+ х)-9 7/12=10 11/12
15 5/12 + x -9 7/12 = 10 11/12
x = 10 11/12-15 5/12 + 9 7/12
x = -4 6/12 + 9 7/12
x = 5 1/12
(15 5/12+ х)-9 7/12=10 11/12
15 5/12 + x -9 7/12 = 10 11/12
x = 10 11/12-15 5/12 + 9 7/12
x = -4 6/12 + 9 7/12
x = 5 1/12