1 4/9 + 3 2/7 3 5/6 - 4/9 5 7/12- 2 2/15 4 11/14-3 2/7 10 1/3 -5 4/9 2 3/5 - 1 6/7

1 4/9 + 3 2/7 = (9 * 1 + 4 / 9) + (7 * 3 + 2 / 7) = 13/9 +23/7 = 91/63 + 207/63 = 298/63 =

= 4 46/63;

3 5/6 - 4/9 = (6 * 3 + 5 / 6) - 4/9 = 23/6 - 4/9 = 69/18 - 8/18 = 61/18 = 3 7/18;

5 7/12 - 2 2/15 = (12 * 5 + 7 / 12) - (15 * 2 + 2 / 15) = 67/12 - 32/15 = 335/60 - 128/60 =

= 207/60 = 3 27/60;  

4 11/14 - 3 2/7 = (14 * 4 + 11 / 14) - (7 * 3 + 2 / 7) = 67/14 - 23/7 = 67/14 - 46/14 = 21/14 =

3/2 = 1 1/2;

10 1/3 - 5 4/9 = (3 * 10 + 1 / 3) - (9 * 5 + 4 / 9) = 31/3 - 49/9 = 93/9 - 49/9 = 44/9 = 4 8/9;

2 3/5 - 1 6/7 = (5 * 2 + 3 / 5) - (7 * 1 + 6 / 7) = 13/5 - 13/7 = 91/35 - 65/35 = 26/35.