Scale 1 : 200, 7 cm on the plan

Step by step

The question

Question: with the scale 1 : 200, how long is 7 cm on the plan for real?

The scale 1 : 200 means: 1 cm on the plan is 200 cm for real.

Everything is 200 times bigger.

1 Multiply both sides

On the plan we have 7 cm.

That is 7 times 1 cm.

So the real length is 7 times 200 cm too.

We multiply both sides by the same number, 7.

200 times 7 is 1400.

So the real length is 1400 cm.

2 Change the unit

1400 cm is a big number.

100 cm make 1 m, so we divide by 100.

1400 divided by 100 is 14.

So it is 14 m.

3 Check

Let's check: go back.

1400 divided by 200 should give the plan length, 7.

We get it again.

So 14 m is right!

Let's look back.

First: multiply both sides.

Then: change the unit.

Last: check.