Ответ:
1)18 5/12 - 7/12 × 1 19/21 - 17/72 × 2/3=17 4/27
2)(6 3/4- 5 1/8:1 9/32)×5/11=1 1/4
Объяснение:
1)7/12 × 1 19/21 = 7/12 × 40/21 = 10/9
17/72 × 2/3 = 17/108
18 5/12 - 10/9= 18 15/36 - 40/36 = 17 11/36
17 11/36 - 17/108=17 4/27
2)(6 3/4-4) ×5/11 =2 3/4×5/11=1 1/4