500
$5.00
0.1 x $50.00 = $5.00
$450.00 X 10% = 4.50, the dress will cost $445.50
5 dollars.
If the dress originally sells for $50.00 and has a $10 discount, you will save $10 off the regular price. This means you will pay $40.00 for the dress after the discount is applied.
Assuming that there is no sales tax, you will multiply 50.00 by 0.10 (that is how you calculate percents) to get 5.00. You subtract this from the original price, to get 45.00. Again, this is assuming no sales tax. :)
20%
60 percent off
$45
You will save 5.00 units of currency.
12 x 100/60: 20%
The original price was $60, and 15% off drops that to $51.