Step by step
The question
Question: change £150 to euros, when £1 = €1.20.
£1 = €1.20. Change £150 to euros.
1 Write the rate
The rate says: 1 pound is worth 1.20 euros.
£1 = €1.20
From pounds to euros, we multiply by 1.20.
Going back, we divide by 1.20.
pounds → euros: × 1.20
euros → pounds: ÷ 1.20
2 Multiply by the rate
Each pound is worth €1.20.
150 pounds are worth 150 times as much.
£150 = 150 × €1.20
150 times 1.20 is €180.
= €180
To multiply decimals: first 150 times 120, as whole numbers.
That is 18000.
Then count the decimal places: 2.
150 × 120 = 18000
2 decimal places: 180
Careful!
Check the direction.
Pounds to euros: we multiply by the rate.
Careful: pounds → euros: × the rate
So £150 is €180.
3 Check
Let's check: change the answer back.
€180 divided by 1.20 is £150.
change it back: €180 ÷ 1.20 = 150
That is what we started with.
So the answer is right!
£150 — what we started with
Let's look back.
First: write the rate.
Then: multiply by the rate.
Last: check.
Answer
Careful: pounds → euros: × the rate