(4 5/12-3 13/24)÷1 3/4+5/6÷5/7

1) 4 5/12 - 3 13/24 = 4 10/24 - 3 13/24 = 3 34/24 - 3 13/24 = 21/24 2) 21/24 : 1 3/4 = 21/24 : 7/4 = 21/24 * 4/7 = (21 и 7 сокращаем, получается 3 и 1; 24 и 4 сокращаем, получается 6 и 1) = 3/6 * 1/1 = = 3/6 * 1 = 3/6 = 1/2 3) 5/6 : 5/7 = 5/6 * 7/5 = (сокращаем две 5) = 1/6 * 7/1 = 7/6 = 1 1/6 4)1/2 + 1 1/6 = (1/2 приводим к знаменателю 6) = 3/6 + 1 1/6 = 1 4/6 = = 1 2/3 Ответ: 1 2/3 (одна целая две трети).

(4(5/12) – 3(13/24) / 1(3/4) + (5/6) / (5/70. 4(5/12) – 3(13/24) = 53/12 – 85/24 = (106 – 85) / 24 = 21/24 = 7/8; 2. (7/8) / 1(3/4) = (7/8) / (7/4) = (7/8) * (4/7) = 1/2. 3. (5/6) / (5/7) = (5/6) * (7/5) = 7/6. 4. 1/2 + 7/6 = 3/6 + 7/6 = 10/6 = 5/3 = 1(2/3).