How to Calculate 30 Percent Off
- 1). Convert the percent to a decimal -- move the decimal point two spots to the left. So, 30 percent would become 0.3.
- 2). Multiply the regular cost of the item by 0.3. If an item has a regular price of $20, for example, multiplying it by 0.3 gets you $6.
- 3). Subtract the amount you got in Step 2 from the regular price to find out what the item will cost once you take off 30 percent. In this example, $6 subtracted from $20 equals $14. So, a $20 item that is marked at 30 percent off will cost you $14. Note that this amount does not include any further taxes that the store might apply at the register.
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