Ratio of 1.2 l to 400 ml Step by Step

Step by step

The question

Question: write the ratio of 1.2 liters to 400 milliliters in its simplest form.

1.2 L : 400 ml

Careful!

The units are not the same: liters and milliliters.

1.2 to 400 would compare different things.

Careful: not 1.2 : 400 ✗

1 Same units

A ratio only compares amounts in the same unit.

We change to the smaller unit, milliliters, so there are no fractions.

1 liter is 1000 milliliters.

1 L = 1000 ml

So 1.2 liters is 1.2 times 1000: 1200 milliliters.

= 1.2 L = 1.2 × 1000 ml = 1200 ml

2 Drop the units

Now the ratio is 1200 milliliters to 400 milliliters.

= 1200 ml : 400 ml

Both are in milliliters.

The same units cancel, so we cross them out.

That leaves 1200 to 400.

= 1200 : 400

3 Simplify

1200 and 400 can both be divided by 400.

We divide both parts by 400.

The ratio stays the same.

= 1200 ÷ 400 : 400 ÷ 400

1200 divided by 400 is 3.

400 divided by 400 is 1.

So the ratio is 3 to 1.

= 3 : 1

4 Check

Let's check: times each part by 400.

We get 1200 milliliters and 400 milliliters again.

3 × 400 = 1200 ml, 1 × 400 = 400 ml

And 1200 milliliters divided by 1000 is 1.2 liters, as in the question.

So the answer is right!

1200 ml = 1200 ÷ 1000 = 1.2 L

Let's look back.

First: same units.

Then: drop the units.

Then: simplify.

Last: check.

Answer