6th Grade Math Textbook, Progress

Sales Tax and Total Cost

12-8

A sales tax is the amount of tax added to the

price of an item by a state or local government.

The rate of sales tax is given as a percent.

The total cost is the sum of the marked, or list,

price and the tax.

A remote control toy costs $224.50, plus 5% sales

tax. Find the sales tax and total cost of the toy.

To find the sales tax, T, write and solve an

equation or a proportion.

To find the total cost, TC, write and solve

the equation: TC
$224.50 $11.23.

TC
$224.50 $11.23

TC
$235.73

The total cost of the toy is $235.73.

• Sales Tax
  Rate of Sales TaxMarked Price
  T
  RMP


• Total Cost
  Marked Price Sales Tax
  TC
  MPT

First estimate: 5% of $220
 2

1

0 $220
$11


Then use one of these methods to find the sales tax.

Method 1

Write and solve an equation.

T
5% of $224.50.

T
5% $224.50

T
$11.225 
$11.23

The sales tax is $11.23.

Write and solve a proportion.

Method 2

part part




whole whole

100 T
$224.50 5

100 T 100 
$1122.50 100

T
$11.225 
$11.23

5

100

T

$224.50

Think

$11.23 is close to the estimate of $11.

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