578 Chapter 6 Percent
shown below in the table. Draw a circle graph for
the data.- EARTH’S SURFACE The surface of Earth is
approximately 196,800,000 square miles. Use the
information in the circle graph
to determine the number of
square miles of Earth’s surface
that are covered with water.
College 57%
Family/Friends 5%
Local bank 18%
Internet 15%
Other 5%Water
70.9% Land
29.1%SECTION 6.3 Applications of Percent
The sales taxon an item is a percent of the
purchase price of the item.
Sales taxsales tax ratepurchase priceAmount = percent base
Notice that the formula is based on the percent
equation discussed in Section 6.2.
Sales tax dollar amountsare rounded to the
nearest cent (hundredth).
The total cost of an item is the sum of its
purchase price and the sales tax on the item.
Total costpurchase pricesales taxDEFINITIONS AND CONCEPTS EXAMPLES
SHOPPING Find the sales tax and total cost of a $50.95 purchase if
the sales tax rate is 8%.Write 8% as a decimal: 8% 0.08.
Do the multiplication.
Round the sales tax to the nearest cent
(hundredth).
Thus, the sales tax is $4.08. The total cost is the sum of its purchase price
and the sales tax.Do the addition.
The total cost of the purchase is $55.03.$55.03
$50.95 $4.08
Total costpurchase pricesales tax rate$4.08
$4.076
0.08$50.95
8 % $50.95
Sales taxsales tax ratepurchase price
Sales tax ratesare usually expressed as a percent. APPLIANCES The purchase price of a toaster is $82. If the sales tax
is $5.33, what is the sales tax rate?
The sales tax of $5.33 is some unknown percent of the purchase price
of $82. There are two methods that can be used to solve this problem.- 43.5 is of what number?
- What percent of 0.08 is 4.24?
- RACING The nitro–methane fuel mixture used to
power some experimental cars is 96% nitro and 4%
methane. How many gallons of methane are needed
to fill a 15-gallon fuel tank? - HOME SALES After the first day on the market,
51 homes in a new subdivision had already sold. This
was 75% of the total number of homes available.
How many homes were originally for sale? - HURRICANE DAMAGE In a mobile home park,
96 of the 110 trailers were either damaged or
destroyed by hurricane winds. What percent is this?
(Round to the nearest 1 percent.) - TIPPING The cost of dinner for a family of five at a
restaurant was $36.20. Find the amount of the tip if
it should be 15% of the cost of dinner. - COLLEGE EXPENSES In 2008, Survey.com
asked 500 college students and parents of students
who needed a loan, where they turned first to pay
for college costs. The results of the survey are