(( х + 2 2/3 ) * 4/15 - 2/3 ) : 8 8/9 = 1/20
((х + 2 2/3 ) * 4/15 - 2/3 = 1/20 * 8 8/9
( х + 2 2/3 ) * 4/15 - 2/3 = 4/9
( х + 2 2/3 ) * 4/15 = 4/9 + 2/3
( х + 2 2/3 ) * 4/15 = 1 1/9
х + 2 2/3 = 1 1/9 : 4/15
х + 2 2/3 = 4 1/6
х = 4 1/6 + 2 2/3
х = 6 5/6
Ответ : х = 6 5/6