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Finding patterns in a multiplication table

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    - [Narrator] We're told here
    is a partially completed
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    multiplication table, so we can see
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    the one times tables, then the twos,
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    threes, fours goes all the way to fives,
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    and they want us to solve six times seven.
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    And they tell us, use the five facts.
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    So that's the ones highlighted in purple
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    as a stepping stone, take five groups
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    and add one more group.
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    So pause this video and have a go at this
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    before we do this together.
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    All right, so we're trying to figure out
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    what six times seven is.
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    So six times seven
    would be right over here
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    on our multiplication table
    and they give us a nice hint.
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    Use the five facts as a stepping stone.
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    Take five groups and add one more group.
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    So what do you mean by that?
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    Well, if you look at this right over here,
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    they tell us that five times seven is 35,
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    five times seven is equal to 35.
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    And if you look at this
    column here, you can see
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    that you can view this as
    adding seven every time.
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    Seven times one is seven,
    seven times two is 14.
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    Seven times three is 21.
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    Seven times four is 28,
    seven times five is 35.
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    So every time we're just adding,
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    every time we're just adding seven
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    when you go down this column,
    so if you wanna figure out
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    what six times seven is
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    or what seven times six is, you just have
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    to add seven more right over here.
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    So 35 plus seven, we
    could do that in our head,
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    or we could just write it out over here.
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    Five plus seven is 12,
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    and then 10 plus 30 is 40.
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    We get 42.
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    So six times seven is equal to 42.
Title:
Finding patterns in a multiplication table
Description:

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Video Language:
English
Team:
Khan Academy
Duration:
01:36

English subtitles

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