решить по действиям: (6 7/12-5 3/8) * 6/29

Решим по действиям, приводя дроби к общему знаменателю:

(6 7/12 - 5 3/8) * 6/29 = 1/4.

1) 6 7/12 - 5 3/8 = 6 - 5 + 7/12 - 3/8 = 1 + (7 * 2) / (12 * 2) - (3 * 3) / (8 * 3) = 1 + 14/24 - 9/24 = 1 + (14 - 9) / 24 = 1 + 5/24 = 1 5/24;

2) 1 5/24 * 6/29 = (1 * 24 + 5) / 24 * 6/29 = (24 + 5) / 24 * 6/29 = 29/24 * 6/29 = (29 * 6) / (24 * 29) = 6/24 = 6 / (6 * 4) = 1/4.

Решим подобный пример:

(1 3/4 - 5/8) * 2/3 = 3/4.

1) 1 3/4 - 5/8 = 1 + 6/8 - 5/8 = 1 + 1/8 = 1 1/8;

2) 1 1/8 * 2/3 = (1 * 8 + 1) / 8 * 2/3 = 9/8 * 2/3 = (3 * 3 * 2) / (2 * 4 * 3) = 3/4.