Percentages are used a lot in life. For example, we see them in tithing, taxes, and store discounts. In this lesson, you will learn how to do calculations using percentages. Remember, in order to do calculations with percentages, we must first convert them into decimals.
Here are the things to remember from this lesson:
- When finding the amount: % as a decimal × total
- When finding the total cost, do the following:
- Find the percentage of the original amount (% as a decimal × original amount)
- When adding the percentage (example: taxes), add the percentage amount to the original amount
- Or, when subtracting the percentage (example: sale), subtract the percentage amount from the original amount
- Pay attention to what the question is asking! Is it asking for how much something will cost after the percentage is added or subtracted, or is it asking how much money the percentage is? Total amount or percentage amount?
- Khan Academy: Percent word problem (04:37 mins)
- How many hours equal 15% of a day? (Video Solution
- What is 35% of 200? (Solution
- If a computer costs $850 and it is on sale for 15% off, how much has the price been reduced? (Solution
- If a dress costs $150 and it is on sale for 20% off, what is the sale price of the dress? (Video Solution
- If a bicycle costs $500 and the sales tax is 6%, what is the total cost of the bicycle with tax included? (Solution