(6 1/15+ 1 4/15)-(8 11/15-4 3/15)=

(6 1/15 + 1 4/15) - (8 11/15 - 4 3/15) = 2 4/5;

Первое действие.

6 1/15 + 1 4/15 = 6 * 15 + 1/15 + 1 * 15 + 4/15 = 91/15 + 19/15 = 91 + 19/15 = 110/15 = 22 * 5/3 * 5 = 22/3 = 1 + 7 * 3/3 = 7 1/3;

Второе действие.

8 11/15 - 4 3/15 = 8 * 15 + 11/15 - 4 * 15 + 3/15 = 131/15 - 63/15 = 131 - 63/15 = 68/15 = 8 + 4 * 15/15 = 4 8/15;

Третье действие.

7 1/3 - 4 8/15 = 7 * 3 + 1/3 - 4 * 15 + 8/15 = 22/3 - 68/15 = 22 * 15/3 * 15 - 68 * 3/15 * 3 = 330/45 - 204/45 = 330 - 204/45 = 126/45 = 14 * 9/5 * 9 = 14/5 = 4 + 2 * 5/5 = 2 4/5.