Basic Mathematics for College Students

Sales tax rates are usually expressed as a percent and, when necessary, sales tax

dollar amounts are rounded to the nearest cent.

536 Chapter 6 Percent

Finding the Sales Tax

The sales tax on an item is a percent of the purchase price of the item.

Sales taxsales tax ratepurchase price

amount = percent  base

  

EXAMPLE (^1) Sales Tax Find the sales tax on a purchase of $56.35 if the
sales tax rate is 5%. (This is the purchase on the sales receipt shown on the previous
page.)
StrategyWe will identify the sales tax rate and the purchase price.
WHYThen we can use the sales tax formula to find the unknown sales tax.
SolutionThe sales tax rate is 5% and the purchase price is $56.35.
This is the sales tax formula.
Substitute 5% for the sales tax rate
and $56.35 for the purchase price.
Write 5% as a decimal: 5% 0.05.
Do the multiplication.
The rounding digit in the hundredths column is 1.
Prepare to round the sales tax to the nearest
cent (hundredth) by identifying the rounding
digit and test digit.
The test digit is 7.
Since the test digit is 5 or greater, round up.
The sales tax on the $56.35 purchase is $2.82. The sales receipt shown on the
previous page is correct.

$2.82

$2.8175

$2.8175

0.05#$56.35

 5 %  $56.35

Sales taxsales tax ratepurchase price

Self Check 1

SALES TAXWhat would the sales

tax be if the $56.35 purchase

were made in a state that has a

6.25% state sales tax?

Now TryProblem 13





5

3

6

1

.3

2

5

 0.05

2.8175

Look at the department store sales receipt once again. Note that the sales tax was

added to the purchase price to get the total cost. This example illustrates the following

formula for total cost.

Finding the Total Cost

The total cost of an item is the sum of its purchase price and the sales tax on

the item.

Total costpurchase pricesales tax

Success Tip It is helpful to see the sales tax problem in Example 1 as a type

of percent problem from Section 6.2.

is of

x  5%  $56.35

What number 5% $56.35?