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Finding the nearest multiple of 1,000, 10,000 and 100,000

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    - [Instructor] We're told
    for the number 372,590,
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    what is the nearest multiple of 100,000?
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    And they give us a little bit
    of a blanket number line here,
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    we have some other questions here,
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    but the way that I'm gonna do it
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    is I'm going to think about
    what multiples of 100,000
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    is this number in between,
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    and then I'm gonna try to roughly see
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    where it sits on that number line.
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    So for example, for 372,590,
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    the hundred thousands
    place is right over here.
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    So this number is between
    300,000 and 400,000.
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    So let me write that here.
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    This is 300,000,
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    for this point on my number line,
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    and I'm gonna make this one, 400,000.
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    Now the number 372,590,
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    where would that be on this number line?
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    Well, if it was 350,000, it
    would be right over here.
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    372,000 is a good bit further,
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    it'd be something like right over here.
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    So if we wanna say
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    what is the nearest multiple
    of a hundred thousand,
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    we just have to say, okay,
    is this where I put 372,590?
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    Is it closer to 400,000 or
    is it closer to 300,000?
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    Well, we can clearly see
    it is more than halfway
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    of the way from 300,000 to 400,000.
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    So the nearest multiple of a
    hundred thousand is 400,000.
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    Now that is an example,
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    why don't you try the next one?
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    What is the nearest multiple of 10,000?
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    Alright, so here we're going
    to do something very similar,
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    but instead of saying multiples
    of a hundred thousand,
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    we're gonna think about
    multiples of 10,000
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    and the ten thousands place,
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    And maybe I'll do this in a new color
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    just for a little bit of variety.
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    We have seven ten-thousands
    in that 70,000 or 72,590.
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    So if we go to the nearest
    10,000, below this number,
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    we are going to be at 370,000.
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    And the nearest 10,000 above this number
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    is going to be 380,000.
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    Now, where does 372,590 sit?
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    Well, if it was 375,000, it
    would be right in the middle.
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    So 372,590
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    is going to be someplace around there.
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    So what's the nearest multiple of 10,000?
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    Well, we're definitely not
    even halfway of the way
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    between 370,000 and 380,000,
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    we're definitely closer to 370,000,
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    so that's what I would write.
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    Let's do this last
    example, maybe in green.
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    What is the nearest
    multiple of a thousand?
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    Once again, pause this video.
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    Have a go at it before
    we do this together.
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    So once again, let's look
    at the thousands place.
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    So if we go to the nearest thousand
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    that's below this number,
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    it would be 372,000.
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    And then the nearest thousand,
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    that or multiple of a
    thousand that's above this
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    would be 373,000.
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    Notice these numbers are
    a hundred thousand apart.
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    These numbers are 10,000 apart.
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    These numbers are a thousand apart.
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    And so where's 372,590?
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    Well, 372,500 would be
    right in the middle,
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    but 372,590 is more than halfway.
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    It's going to be roughly right over there,
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    so you can see that it's closer to 373,000
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    than it is to 372,000.
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    So we would go right over there.
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    You might be wondering, what
    if we were right in the middle?
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    What would we say we are nearest to?
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    Well, you might make an argument
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    that we're equally near to either end,
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    but as you go further in your math career,
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    you'll learn that when people
    wanna think about this,
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    they come up with certain rules
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    when you are stuck in
    that tie-like situation.
Title:
Finding the nearest multiple of 1,000, 10,000 and 100,000
Description:

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Video Language:
English
Team:
Khan Academy
Duration:
03:41

English subtitles

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