5/7*14/25 4целых 2/9*1целых 5/19 8целых 3/11*1целых 7/15*10 /13 13/18: 26/27 3целых 8/9: 2целых 13/18 4,3: 7 1/6 (5 3/4-4 8/9)*2+67 1/2: 2 1/7 1 33/67*((5 8/9-3 5/27+1 5/6)*9/28-(2 9/16+3 5/12)*2/15)

5/7 · 14/25=2/5

4 2/9 · 1 5/19=38/9 · 24/19=48/9=5 3/9=5 1/3

8 3/11 · 1 7/15 · 10/13=91/11·22/15·10/13=7/1·2/15·10/1=7·2/5·2=28/5=5 3/5

13/18 : 26/27=13/18 · 27/26=1/18·27/2=27/36

3 8/9 : 2 13/18=35/9 : 49/18= 35/9 · 18/49=5/1 · 2/7=10/7=1 3/7

4,3 : 7 1/6=43/10 : 43/6=43/10 · 6/43=6/10=3/5

(5 3/4 - 4 8/9)·2 + 67 1/2 : 2 1/7=(23/4 - 44/9)·2+135/2 : 15/7=
=23/2-88/9+135/2·7/15=23/2-88/9+9/2·7/1=23/2-88/9+63/2=43-88/9=387/9-88/9=299/9=33 2/9