3/8×4/5:9/10 2)6/7:3/5×1целая 2/5

2 2/11 х 13/8 : 3/4 =   1) 2 2/11 х 13/8 = 24/11 х 13/8 = 39/11. 2) 39/11 : 3/4 = 39/11 х 4/3 =52/11 = 4 8/11. 

3/5 х ( 2 2/3 : 3 1/5) =.   1) 2 2/3 : 3 1/5 = 8/3 : 16/5 = 8/3 х 5/16 =15/2. 2) 3/5 х 15/2='9/2 = 4 1/2

3/8 х 4/5 : 9/10 = 1/3 1) 3/8 х 4/5 = 3/10, 2) 3/10 : 9/10 = 3/10 х 10/9 = 1/3. Теперь второй пример: 6/7 : 3/5 х 1 2/5 =2. 1) 6/7 : 3/5 = 6/7 х 5/3 = 10/7, 2) 10/7 х 1 2/5 = 10/7 х 7/5 = 2.