Step by step
The question
Question: change £35.50 to dollars, when £1 = $1.27.
£1 = $1.27. Change £35.50 to dollars.
1 Write the rate
The rate says: 1 pound is worth 1.27 dollars.
£1 = $1.27
From pounds to dollars, we multiply by 1.27.
Going back, we divide by 1.27.
pounds → dollars: × 1.27
dollars → pounds: ÷ 1.27
2 Multiply by the rate
Each pound is worth $1.27.
35.5 pounds are worth 35.5 times as much.
£35.50 = 35.5 × $1.27
35.5 times 1.27 is $45.09.
≈ $45.09
To multiply decimals: first 355 times 127, as whole numbers.
That is 45085.
Then count the decimal places: 3.
355 × 127 = 45085
3 decimal places: 45.085
Careful!
Check the direction.
Pounds to dollars: we multiply by the rate.
Careful: pounds → dollars: × the rate
So £35.50 is about $45.09.
3 Check
Let's check: change the answer back.
$45.09 divided by 1.27 is about £35.50.
change it back: $45.09 ÷ 1.27 ≈ 35.50
That is what we started with.
So the answer is right!
£35.50 — what we started with
Let's look back.
First: write the rate.
Then: multiply by the rate.
Last: check.
Answer
Careful: pounds → dollars: × the rate