Math with Mr. J: Calculating Sales Tax and Final Price

Overview

• This lecture covers how to calculate sales tax and determine the final price including tax.
• Sales tax rates vary by country, state, and may include local taxes.

Key Concepts

1. Converting Percent to Decimal

• Sales tax is typically given as a percentage.
• Convert the percentage to a decimal by dividing by 100 or moving the decimal point two places to the left.
• Example: 8% becomes 0.08.

2. Calculating Sales Tax

• Sales tax is calculated by multiplying the original price by the decimal tax rate.
• Alternatively, use a calculator with a percent button to multiply directly by the percentage.

3. Calculating Final Price

• Add the calculated sales tax to the original price to get the final price.

Example Calculations

Example 1

• Original Price: $75
• Sales Tax Rate: 8%
  • Convert to decimal: 8% → 0.08
  • Sales tax: $75 x 0.08 = $6
• Final Price: $75 + $6 = $81

Example 2

• Original Price: $349.99
• Sales Tax Rate: 6.75%
  • Convert to decimal: 6.75% → 0.0675
  • Sales tax: $349.99 x 0.0675 = $23.624325
  • Round to nearest cent: $23.62
• Final Price: $349.99 + $23.62 = $373.61

Important Notes

• Always convert the sales tax rate from percent to decimal unless using a calculator with a percent function.
• Round the sales tax to the nearest cent when dealing with currency.

Conclusion

• Calculate the sales tax by multiplying the original price by the tax rate.
• Add the sales tax to the original price to find the final price including tax.

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• End Note: Ensure accuracy in conversions and calculations for precise financial management.