Step by step
The question
Question: A jacket costs $80.
It is 25% off, then 8% sales tax is added.
What is the final price?
1 Find the discount
Percent means out of 100.
So 25% is 25 divided by 100: 0.25.
The point moves 2 places to the left.
The discount is 25% of $80.
"Of" means times: 0.25 times $80.
That is $20.
To multiply decimals: first 25 times 80, as whole numbers.
That is 2000.
Then count the decimal places: 2.
So it is 20.00.
Careful!
We can't just take 8% from 25%.
The tax is on the sale price, not on $80.
2 Take it off
A discount comes off the price.
$80 minus $20 is $60.
3 Find the tax
Percent means out of 100.
So 8% is 8 divided by 100: 0.08.
The point moves 2 places to the left.
The tax is 8% of $60.
"Of" means times: 0.08 times $60.
That is $4.80.
To multiply decimals: first 8 times 60, as whole numbers.
That is 480.
Then count the decimal places: 2.
So it is 4.80.
4 Add it on
The tax is added to the price.
$60 plus $4.80 is $64.80.
So the final price is $64.80.
5 Check
Let's check another way: we pay 100% minus 25%: 75% of the price.
0.75 times $80 is $60.
Then: we pay 100% plus 8%: 108% of the price.
1.08 times $60 is $64.80.
The same.
So the answer is right!
Let's look back.
First: find the discount.
Then: take it off.
Then: find the tax.
Then: add it on.
Last: check.