Пошаговое объяснение:

253.

4/7=12/21

12/21>5/21; 4/7>5/21

3/10=9/30

8/15=16/30

9/30<16/30; 3/10<8/15

13/16=26/32

26/32>15/32; 13/16>15/32

11/12=44/48

13/16=39/48

44/48>39/48; 11/12>13/16

254.

2/15=10/75

4/25=12/75

10/75<12/75; 2/15<4/25

2/3=20/30

1/2=15/30

2/5=12/30

20/30>15/30>12/30

2/3>1/2>2/5

1/6=2/12

5/6=10/12

1/4=3/12

2/12<3/12<10/12

1/6<1/4<5/6