5 5/12*4/13-2 5/8*3/14

5 5/12 * 4/13 - 2 5/8 * 3/14 = 1 5/48.

1) 5 5/12 * 4/13 = (5 * 12 + 5) / 12 * 4/13 = (60 + 5) / 12 * 4/13 = 65/12 * 4/13 = (65 * 4) / (12 * 13) = (13 * 5 * 4) / (4 * 3 * 13) = 5/3 = 1 (5 - 1 * 3) / 3 = 1 (5 - 3) / 3 = 1 2/3;

2) 2 5/8 * 3/14 = (2 * 8 + 5) / 8 * 3/14 = (16 + 5) / 8 * 3/14 = 21/8 * 3/14 = (21 * 3) / (8 * 14) = (7 * 3 * 3) / (8 * 7 * 2) = (3 * 3) / (8 * 2) = 9/16;

3) 1 2/3 - 9/16 = (1 * 3 + 2) / 3 - 9/16 = (3 + 2) / 3 - 9/16 = 5/3 - 9/16 = (5 * 16) / (3 * 16) - (9 * 3) / (16 * 3) = 80/48 - 27/48 = (80 - 27) / 48 = 53/48 = 1 5/48.