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| The Meaning of Percent |
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Unit
4 > Lesson 1 of 9 |
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Problem:
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What fraction of each grid is shaded?
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Each grid above has 100 boxes. For each grid, the
ratio
of the number of shaded boxes to the total number of boxes can be represented as a fraction.
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| Comparing Shaded Boxes to Total Boxes |
| Grid |
Ratio |
Fraction |
| 1 |
96 to 100 |
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| 2 |
9 to 100 |
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| 3 |
77 to 100 |
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We can represent these fractions as percents using the symbol %.
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Definition:
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A percent is a ratio whose second term is 100. Percent means parts per hundred. The
word comes from the Latin phrase per centum, which means per hundred. In mathematics, we use the
symbol % for percent.
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Let's look at our comparison table again. This time the table includes percents.
| Comparing Shaded Boxes to Total Boxes |
| Grid |
Ratio |
Fraction |
Percent |
| 1 |
96 to 100 |
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96% |
| 2 |
09 to 100 |
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09% |
| 3 |
77 to 100 |
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77% |
Let's look at some examples in which we are asked to convert between ratios, fractions, decimals and percents.
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Example 1:
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Write each ratio as a fraction, a decimal, and a percent:
4 to 100, 63 to 100, 17 to 100
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| Solution |
| Ratio |
Fraction |
Decimal |
Percent |
| 04 to 100 |
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.04 |
04% |
| 63 to 100 |
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.63 |
63% |
| 17 to 100 |
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.17 |
17% |
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Example 2:
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Write each percent as a ratio, a fraction in lowest terms, and a decimal:
24%, 5%, 12.5%
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| Solution |
| Percent |
Ratio |
Fraction |
Decimal |
| 24% |
24 to 100 |
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.240 |
| 05% |
05 to 100 |
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.050 |
| 12.5% |
12.5 to 100 |
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.125 |
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Example 3:
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Write each percent as a decimal:
91.2%, 4.9%, 86.75%
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| Solution |
| Percent |
Decimal |
| 91.2% |
.9120 |
| 04.9% |
.0490 |
| 86.75% |
.8675 |
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Summary:
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A percent is a ratio whose second term is 100. Percent means parts per
hundred and we use the symbol % to represent it. In this lesson, we learned how to
convert between ratios, fractions, decimals and percents.
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Exercises
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Directions: Read each question below. Select your answer by clicking on its button. Feedback to your answer
is provided in the RESULTS BOX. If you make a mistake, choose a different button.
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1. Which of the following is equal to
?
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2. Which of the following is equal to 21.8%?
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3. Which of the following is equal to 150%
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4. Which of the following is equal to .0179?
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5. Which of the following is equal to 56.28%?
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