How to Calculate Sales Tax without a Calculator | Calculating Sales Tax by Hand | Math with Mr. J

Summary

In the video 'Math with Mr. J,' the host teaches viewers how to manually calculate sales tax and the total cost of a purchase. The example uses a price of $59.49 with a 7.5% sales tax. The process involves converting the percentage to a decimal, multiplying it by the price, and then adding the tax to the original price to find the total cost. The host demonstrates each step in detail, including rounding the sales tax to the nearest cent, resulting in a total cost of $63.95.

Takeaways

• 🧮 To calculate sales tax by hand, you first need to convert the sales tax rate from a percentage to a decimal.
• 🔢 The conversion from percentage to decimal is done by dividing by 100 and moving the decimal point two places to the left.
• ✅ The decimal form of a 7.5% sales tax rate is 0.075.
• 🛒 To find out how much sales tax you owe on an item, multiply the item's price by the tax rate in decimal form.
• 📝 When multiplying a decimal by a whole number, you can ignore the decimal for the multiplication and then place it in the correct position in your final answer.
• 📑 The number of digits to the right of the decimal in your final answer should match the number of digits to the right of the decimal in the original price.
• 💵 When dealing with money, it's important to round your sales tax calculation to the nearest hundredth (two decimal places).
• 🔄 If the hundredths place is 5 or more, round up; if it's less than 5, round down.
• 💲 To find the total cost of an item including sales tax, add the calculated sales tax to the original price of the item.
• 📈 When adding decimals, align the decimal points and proceed with the addition as you would with whole numbers.

Q & A

What is the main topic of the video?

The main topic of the video is how to calculate sales tax by hand without using a calculator.

What is the example sales price used in the video?

The example sales price used in the video is $59.49.

What is the sales tax rate used in the example?

The sales tax rate used in the example is 7.5 percent.

How does the video demonstrate converting a percentage to a decimal?

The video demonstrates converting a percentage to a decimal by dividing the percentage by 100 and moving the decimal point two places to the left.

What is the decimal equivalent of the 7.5 percent sales tax rate as shown in the video?

The decimal equivalent of the 7.5 percent sales tax rate is 0.075.

How does the video approach multiplying the sales price by the tax rate?

The video multiplies the sales price by the tax rate in decimal form, taking care to place the decimal in the correct position in the final answer.

What is the result of multiplying $59.49 by the tax rate of 0.075 as shown in the video?

The result of multiplying $59.49 by the tax rate of 0.075 is $4.46, which is the sales tax amount.

How does the video ensure the correct placement of the decimal in the sales tax calculation?

The video ensures the correct placement of the decimal by counting the number of digits to the right of the decimal in the original price and matching that in the final sales tax amount.

What rounding rule is applied to the sales tax calculation in the video?

The video applies the standard rounding rule where if the digit to the right of the last desired decimal place is 5 or more, the last digit is increased by one.

How does the video calculate the total cost including sales tax?

The video calculates the total cost by adding the original price to the calculated sales tax amount, ensuring the decimals are aligned during the addition.

What is the final price including sales tax as presented in the video?

The final price including sales tax is $63.95.