$1 = €0.90. Change €45 to dollars.

Step by step

The question

Question: change €45 to dollars, when $1 = €0.90.

1 Write the rate

The rate says: 1 dollar is worth 0.90 euros.

From dollars to euros, we multiply by 0.90.

Going back, we divide by 0.90.

2 Divide by the rate

Each $1 gives €0.90.

So we find how many €0.90 fit in €45: we divide by 0.90.

Careful!

From euros back to dollars goes the other way.

We divide, not multiply.

45 divided by 0.90 is $50.

To divide by 0.90, we move the point in both numbers 2 places: 4500 divided by 90.

So €45 is $50.

3 Check

Let's check: change the answer back.

$50 times 0.90 is €45.

That is what we started with.

So the answer is right!

Let's look back.

First: write the rate.

Then: divide by the rate.

Last: check.