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Converting decimals to percents example 2 | Decimals | Pre-Algebra | Khan Academy

  • 0:01 - 0:07
    Let's see if we can write
    1.501 as a percentage.
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    Now we really just want
    to write this quantity
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    as something over 100.
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    So what we can do is
    we can say that this
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    is the same thing
    as 1.501 over 1.
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    We haven't changed its value.
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    And let's multiply
    it times 100/100.
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    When we do this product-- and
    I haven't changed the value.
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    This is just multiplying
    something times 1.
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    But when we do it, we're
    going to change the way
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    that we're representing it.
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    The denominator now is
    going to be 1 times 100.
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    So that's pretty
    straightforward.
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    That's just going to be 100.
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    And then the
    numerator, we're going
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    to want to multiply
    1.501 times 100.
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    And so if we multiply
    this times 10,
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    we would move the
    decimal one over.
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    We want to multiply
    it by 100, so we
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    want to multiply by 10 again.
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    So we're going to move the
    decimal over to the right
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    twice.
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    We're multiplying
    it by 10 twice,
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    or you're multiplying it by 100.
  • 0:58 - 0:59
    This is multiplying by 10.
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    This is multiplying by 100.
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    So this is where the
    decimal's going to sit now.
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    So we're going to get 150.1.
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    And so we've rewritten the
    1.501 as 150.1 over 100,
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    or 150.1 per 100.
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    Let me write that.
  • 1:15 - 1:23
    150.1 per 100, which
    is the same thing
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    as 150.1 per cent, which is
    the same thing as 150.1%.
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    And we're done.
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    And, essentially, all
    you're doing-- if you really
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    want to simplify the process--
    we're multiplying this
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    by 100 to get 150.1.
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    And then we're saying,
    that is the percentage.
  • 1:44 - 1:46
    So you want to make sure that
    you write the percent there
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    or the percent symbol.
Title:
Converting decimals to percents example 2 | Decimals | Pre-Algebra | Khan Academy
Description:

Think of a mixed numbers as a number AND a fraction. You can add numbers....you can add fractions with like denominators. Therefore, you can add mixed numbers! Watch.

Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/mixed-number-add-sub-pre-alg/e/adding_subtracting_mixed_numbers_0.5?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra

Watch the next lesson: https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/mixed-number-add-sub-pre-alg/v/adding-subtracting-mixed-numbers-0-5-ex-2?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra

Missed the previous lesson?
https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/mixed-number-add-sub-pre-alg/v/subtracting-mixed-numbers-word-problem?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra

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Video Language:
English
Team:
Khan Academy
Duration:
01:48

English subtitles

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