The ratio 2.5 metres to 70 centimeters can be written in the form 1:n

fine the value of n

First analyze your data.

2.5 meters to 70 centimeters.

And you have to convert 1 meters to n centimeters.

So make a proportion.

2.5 / 70 = 1/n

The 2.5 and the one are both on top because it is the same unit, meters.

Then multiply and divide like so ...

70*1=70 now 70/2.5=28

So 28=n.