6th Grade Math Textbook, Fundamentals

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7-1

Key Concept

Percent

A is a ratio or comparison of a quantity to 100.

n%

nper hundred or nto 100

n

100

part

whole

percent (%)



So 107 70%.

70

100

7 • 10

10 • 10

7

10

7

(^110)
Update your skills. See page 410.
Percents
Objective To model percents• To write percents as equivalent ratios and to
write ratios as equivalent percents
Some turtles lay their eggs on beaches and bury them
in the sand to protect them from predators. A nest
of turtle eggs may contain as many as 100 eggs.
If 48 out of 100 turtle eggs in a nest produce hatchlings,
what percent of the eggs in the nest produce hatchlings?

To find the percent of the eggs in the nest that produce

hatchlings, express the ratio 48 : 100 as a percent.

48 out of 100 48 : 100

 Write as a fraction with a denominator of 100.

48% Write as a percent.

So 48% of the turtle eggs produce hatchlings.

When the second term of a ratio is 10 or 1000, you can use

mental math to find an equivalent fraction with a denominator

of 100 and then rename that fraction as a percent.

48

100

Think

10 • 10  100

Remember: 100 n n%

part whole



So^70 7%.

1000

70

1000

7

100

70  10

1000  10

70

1000

2



So^87 8.7%.

1000

8.7

100

87  10

1000  10

87

1000

87

1000

3

Write each as a percent.

Think

1000  10  100