Main Idea

NGSSS

Key Concept:Percents and Decimals

Example 1:Percents as Decimals

Example 2:Percents as Decimals

Example 3: Decimals as Percents

Example 4: Decimals as Percents

Example 5: Fractions as Percents

Example 6: Fractions as Percents

Example 7: Compare Rational Numbers

Example 8: Order Rational Numbers

Five-Minute Check

• Compare and order rational numbers.

MA.8.A.6.4 Perform operations on real numbers (including integer exponents, radicals, percents, scientific notation, absolute value, rational numbers, and irrational numbers) using multi-step and real world problems.

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Percents as Decimals

Write 52% as a decimal.

52% = 52%Divide by 100.

= 0.52Remove the percent symbol.

Answer: 0.52

A. 0.004

B. 0.04

C. 0.4

D. 4.0

Write 4% as a decimal.

Write 245% as a decimal.

Percents as Decimals

245% = 245%Divide by 100.

= 2.45Remove the percent symbol.

Answer: 2.45

A. 0.032

B. 0.32

C. 3.2

D. 32

Write 320% as a decimal.

Decimals as Percents

Write 0.3 as a percent.

0.3= 0.30Multiply by 100.

= 30% Add the percent symbol.

Answer: 30%

A. 0.09%

B. 0.9%

C. 9%

D. 90%

Write 0.09 as a percent.

Write 2.71 as a percent.

Decimals as Percents

2.71= 2.71Multiply by 100.

= 271% Add the percent symbol.

Answer: 271%

A. 1.045%

B. 10.45%

C. 104.5%

D. 1,045%

Write 1.045 as a percent.

Fractions as Percents

Method 1 Use a proportion.

Write as a percent.

First write as a decimal. Then write as a percent.

Method 2 Write as a decimal.

Fractions as Percents

Answer: So, or 75%.

0.75

= 75%

A. 17%

B. 20%

C. 68%

D. 85%

Write as a percent.

Fractions as Percents

Write as a percent.

– 640

– 3640

Answer: So, .

0.166_

– 364

0.166 …

Write as a percent.

A.

B.

C.

D.

Compare Rational Numbers

Answer: Marysville

POLITICS In Sun City, 0.45 of the voters are Democrats. In Marysville, 48% of the voters are Democrats. In which town is there a greater portion of Democrats?

Since 0.45 = 45% and 45% < 48%, Marysville has a greater portion of Democrats.

A. There were more hound dogs than sporting dogs.

B. There were more herding dogs than hound dogs.

C. There were more sporting dogs than hound dogs.

D. There were the same number of sporting dogs and hound dogs.

DOGS In a dog show, of the dogs were

hounds, 17% were sporting dogs, and 13 out of

125 were herding dogs. Which is a true

statement?

Order Rational Numbers

From least to greatest, the percents are 7%, 70%, 76%, and 77%.

Answer: So, from least to greatest, the numbers

are

and 0.77.

Order 0.77, from least to greatest.

A.

B.

C.

D.

Order and from least to greatest.

A. 0.023

B. 0.23

C. 2.3

D. 23

Write 23% as a decimal.

A. 0.00106

B. 0.0106

C. 0.106

D. 1.06

Write 106% as a decimal.

A. 0.062%

B. 0.62%

C. 6.2%

D. 62%

Write 0.0062 as a percent.

A. 0.575%

B. 5.75%

C. 57.5%

D. 575%

Write as a percent.

A.

B. 40%

C. 44%

D.

Write as a percent.

Choose the fraction that is less than 23%.

A.

B.

C.

D.

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