Answer:

7:40

Step-by-step explanation:

1.2m=120cm (m to cm= x 100)

Width=21cm

Length=120cm

21:120=21/120

21/120=7/40

Therefore,7:40 is the ratio.

Hope that helped :)

Step-by-step explanation:

Here,

The given length of the rectangular sheet of paper is 1.2m

And the width of the paper is 21 cm.

Now, convert the length of the paper from the meter into centimetres

Length of paper = 1.2 m 100 cm = 1.2 x

Length of paper = 120 cm.

To find the ratio of the width of the paper to its length we have

The required ratio = width of paper length of paper

Hence, the required ratio is 7: 40.