Ответ:
21 2/3
Пошаговое объяснение:
(7-5 3/8)•8+1 12/13:5/26•(1/5+2/3) = 21 2/3
По действиям:
1. 7 - 5 3/8 = 1 5/8
2. 1 5/8 * 8 = 13/8 * 8 = 13
3. 1 12/13 : 5/26 = 25/13 * 26/5 = 10
4. 1/5 + 2/3 = (1*3+2*5)/15 = 13/15
5. 10 * 13/15 = 130/15 = 8 2/3
6. 13 + 8 2/3 = 21 2/3