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Converting decimals to fractions 1 (ex 1)

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    Let's see if we can write 0.15 as a fraction.
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    So the important thing here is to look at
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    what place these digits are in.
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    So this 1 right over here, this is in the tenths place.
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    So you could view that as 1 × 1/10.
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    This 5 right over here is in the hundredths place.
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    So you could view that as 5 × 1/100.
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    So if I were to rewrite this,
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    I can rewrite this as the sum of –
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    this 1 represents 1 × 1/10,
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    So that would literally be 1/10 – plus –
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    And this 5 represents 5 × 1/100.
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    So it would be plus 5/100.
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    And if we want to add them up,
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    if we want to find a common denominator –
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    (The common denominator is 100.)
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    Both 10 and –
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    [100] is the least common multiple.
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    [100] is a multiple of both 10 and 100.
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    So we can rewrite this as something over 100 plus something over 100.
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    This isn't going to change. This was already 5/100.
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    If we multiply the denominator here by 10 –
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    (That's what we did. We multiplied it by 10.)
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    – then we're going to have to multiply this numerator by 10.
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    And so this is the same thing as 10/100.
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    And now we're ready to add.
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    This is the same thing as 10 + 5, is 15/100.
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    And you could have done that
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    a little bit quicker just by inspecting this.
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    You would say, "Look!
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    My smallest place right over here is in the hundredths place."
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    Instead of calling this 1/10, I could call this literally 10/100.
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    Or, I could say this whole thing is 15 100ths.
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    And now if I want to reduce this to lowest terms,
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    we can – Let's see,
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    Both the numerator and the denominator are divisible by 5.
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    So let's divide them both by 5.
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    And so the numerator, 15, divided by 5 is 3.
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    The denominator, 100, divided by 5 is 20.
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    And that's about as simplified as we can get.
Title:
Converting decimals to fractions 1 (ex 1)
Description:

Converting decimals to fractions 1 (ex 1)

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Video Language:
English
Duration:
01:56

English subtitles

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