Найдите значение выражения (6 7/9 - a)- (a- 1 7/15), если а=2 2/3

(6 7/9 - 2 2/3) - (2 2/3 - 1 7/15) = 2 41/45
1) 6 7/9 - 2 2/3 = 6 7/9 - 2 6/9 = 4 1/9
2) 2 2/3 - 1 7/15 = 2 10/15 - 1 7/15 = 1 3/15 = 1 1/5
3) 4 1/9 - 1 1/5 = 4 5/45 - 1 9/45 = 3 50/45 - 1 9/45 = 2 41/45