1 cm = 0.0 1 m

25cm = 0.25m.

0.25/5= 1/20

So the answer is 1/20.

Question 2: Hardcover book =32 yuan

Paperback book =32- 12=20 yuan

Paperback book/hardcover book =20/32=5/8

So the answer is 5/8.

Question 3: Pass the score first:

9/ 14=36/56,

36- 15=2 1

So the answer is: 2 1

Question 4: Pass the score first:

4/ 19= 16/76,

So the answer is: 16.

Question 5: The simplest number is 4/5.

There are 4*5=20,

The product of numerator and denominator is 25 times of 500/20 = 20,

So the numerator and denominator are magnified five times (that is, 25 under the root sign), 20/25.

So the answer is: 20/25.

Question 6: What has not been repaired is: (15-5) kilometers,

Not repaired/repaired =( 15-5)/ 15=2/3.

So the answer is: 2/3

If it helps, thank you for your adoption!