How to Calculate a Discount and Sale Price | Math with Mr. J

Summary

In this video, Mr. J teaches viewers how to calculate discounts and final sale prices. He demonstrates the process step by step using two examples. First, he shows how to calculate a 15% discount on $68, resulting in a final price of $57.80. Next, he explains how to calculate a 40% discount on $219.95, bringing the price down to $131.97. Mr. J emphasizes the importance of converting percentages to decimals and provides tips for using calculators. By the end, viewers learn the method for calculating discounts and applying them to determine sale prices.

Takeaways

• 😀 Percentages represent 'per 100' and need to be converted to decimals for calculations.
• 😀 To convert a percentage to a decimal, move the decimal point two places to the left.
• 😀 For example, 15% becomes 0.15 after converting to decimal form.
• 😀 To calculate the discount, multiply the original price by the decimal form of the percentage.
• 😀 For example, to calculate 15% off $68, multiply 68 by 0.15 to get a $10.20 discount.
• 😀 After calculating the discount, subtract it from the original price to find the final sale price.
• 😀 In the example of $68 with a 15% discount, the final sale price is $57.80 after subtracting $10.20.
• 😀 Percentages can also be calculated using a calculator's percent button, avoiding manual conversion.
• 😀 To find 40% off $219.95, multiply 219.95 by 0.40, which results in a $87.98 discount.
• 😀 When subtracting decimals, line up the decimal points to ensure accurate results.
• 😀 After applying the discount to $219.95, the final sale price is $131.97.
• 😀 Mastering the conversion of percentages and applying them to calculate discounts is a valuable skill for understanding sales prices.

Q & A

What is the first step in calculating a discount?

The first step is to calculate the discount amount by multiplying the original price by the rate of discount (converted to decimal form).

How do you convert a percentage into a decimal for calculations?

To convert a percentage into a decimal, you divide the percentage by 100, or simply move the decimal two places to the left.

What is the decimal form of 15%?

The decimal form of 15% is 0.15, which is found by moving the decimal two places to the left from 15.

How do you calculate the discount for a price of $68 with a 15% discount?

To calculate the discount, multiply $68 by 0.15 (the decimal form of 15%). The result is $10.20.

What is the final sale price after applying a 15% discount to a $68 item?

After applying a 15% discount to $68 (which is $10.20 off), the final sale price is $57.80.

What is the discount amount for an item priced at $219.95 with a 40% discount?

To calculate the discount, multiply $219.95 by 0.40 (the decimal form of 40%). The discount amount is $87.98.

How do you subtract the discount from the original price to find the final sale price?

To find the final sale price, subtract the discount from the original price. For example, $219.95 minus $87.98 gives a final sale price of $131.97.

What is the importance of lining up decimals when subtracting amounts with cents?

Lining up the decimals ensures that you are subtracting the correct place values (dollars from dollars and cents from cents), which is crucial for accurate calculations.

What can you do if you don’t have a calculator that can directly handle percentage calculations?

You can manually convert the percentage to a decimal and then multiply it by the original price to calculate the discount.

What is the key takeaway from this video about calculating discounts and sale prices?

The key takeaway is that by converting percentages to decimals and following the simple steps of multiplying the original price by the discount rate, you can easily calculate both the discount and the final sale price.