# Help Zone

### Student Question

Secondary I • 1yr.

Hello, how do I calculate a 20% discount on a sweater that costs $10? thank you Mathematics {t c="richEditor.description.title"} {t c="richEditor.description.paragraphMenu"} {t c="richEditor.description.inlineMenu"} {t c="richEditor.description.embed"} ## Explanations (1) • Explanation from Alloprof Explanation from Alloprof This Explanation was submitted by a member of the Alloprof team. Options Team Alloprof • 1yr. Hi First of all, a discount indicates a decrease in the price, so you will pay less than$ 10 for the sweater.

Here is a trick you can use:

You take the number 1 and you put a +/- after it, like this:

1 +/-

If you have a tax, we do 1+

If we have a discount we do 1-

In this case, we have a 20% discount (20% corresponds to 0.2, because we make 20/100). In consequence, we do 1-0.2 = 0.8.

After this step, we only need to multiply 10 by 0.8 and we get the answer!

Hope to have helped you!