A store advertises 25% off a $31 shirt. What is the sale price
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A store advertises 25% off a 31 dollar shirt. What is the sale price? When a store offers a 25 percent discount, it means the customer pays 25 percent less than the original price. Our goal is to find the final price after applying this discount.
To work with percentages mathematically, we convert them to decimals. To convert 25 percent to a decimal, we write it as a fraction: 25 over 100. This fraction equals 0.25 in decimal form. This conversion is essential for our calculations.
Now we calculate the dollar amount of the discount. We multiply the original price, 31 dollars, by the decimal form of the percentage, 0.25. This gives us 31 times 0.25 equals 7.75 dollars. This 7.75 dollars is the amount of money saved, not the final price the customer pays.
To find the final sale price, we subtract the discount amount from the original price. That is, 31 dollars minus 7.75 dollars equals 23.25 dollars. Therefore, the sale price of the shirt is 23 dollars and 25 cents.
We can verify our answer using an alternative approach. If 25 percent is taken off, then 75 percent of the original price remains. So we can calculate 75 percent of 31 dollars directly. Converting 75 percent to a decimal gives us 0.75. Multiplying 31 by 0.75 equals 23.25. This confirms our previous answer of 23 dollars and 25 cents.
Let's try another example to solidify our understanding. A 40 dollar item with 30 percent off. First, we convert 30 percent to a decimal: 0.30. Next, we calculate the discount amount: 40 times 0.30 equals 12 dollars. Finally, we subtract the discount from the original price: 40 minus 12 equals 28 dollars. So the sale price is 28 dollars. As practice, try finding the sale price of a 25 dollar item with 15 percent off.