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Time word problem

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    Susan has 96 minutes to
    complete a test at school.
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    The test begins at 1:59 PM.
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    And Susan has volleyball
    practice at 4:00 PM.
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    How much time will Susan have
    between the end of the test
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    and the beginning of
    volleyball practice?
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    Let's think about
    this a little bit.
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    So the test begins at 1:59.
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    So it's a very strange
    time to begin a test,
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    but let's just go with that.
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    So let me draw a
    little time line here.
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    So let's say that
    this is 2 o'clock PM.
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    Then we're going
    to have 3:00 PM.
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    Then we're going to have 4
    o'clock PM, which is also
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    when volleyball practice begins.
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    So this is volleyball practice.
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    It's going to start then
    and then go on from 4:00 PM.
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    And then the test
    begins at 1:59.
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    So let me continue
    the number line.
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    So this right over
    here is 1:00 PM.
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    So the test is going to begin at
    1:59, so 1 minute before 2 PM.
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    We know that there are
    60 minutes in an hour.
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    So 1:59 is 1 minute
    before 2:00 PM.
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    So I'm not drawing it
    completely it scale,
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    but this right over
    here is 1:59 PM.
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    So we use 1 minute
    to get to 2:00 PM.
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    And then, let's see, we have
    to get up to 96 minutes.
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    So then you get another 60
    minutes to go to 3:00 PM.
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    So, so far, we've
    used a cumulative 61.
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    So this is 1 minute.
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    So this is how long the
    test has been going on
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    since the beginning.
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    So 1 minute by 2:00 PM,
    61 minutes by 3:00 PM.
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    If we go all the way to 4:00 PM,
    that's going to be another 60.
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    That'd be 121 minutes, which
    is longer than the actual test.
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    So we know that the
    entire test is 96 minutes.
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    So we're going to get
    to some point right
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    over here, some point like this.
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    That's 96 minutes.
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    And what we need to figure
    out is, is what is left over?
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    What is this distance
    right over here?
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    Or what is this
    time, this difference
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    in time right over here?
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    And so to figure
    that out, we had
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    to figure out the time at
    which 96 minutes have passed
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    since the beginning of the exam.
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    So at 3 o'clock, 61
    minutes have passed.
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    And so if we, if we say
    well how many more minutes
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    have to go on for
    the end of the test?
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    It's going to be 96 minus 61.
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    So the amount of time that
    elapses past 3 minutes
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    is 96 minus 61,
    which is 35 minutes.
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    So this right over here
    is going to be 3:35.
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    And so now our question
    is, how much time is there
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    between 3:35 and 4:00 PM?
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    Well, once again, 60
    minutes in an hour.
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    4:00 PM is essentially
    the 60th minute.
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    So if we take 60
    minus 35, we get 2:25.
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    So she has a total of 25
    minutes remaining after the test
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    before she has to get
    to volleyball practice.
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    Just as a review.
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    One minute between 1:59
    and 2:00, then another 60.
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    That gets us to
    61 total minutes.
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    Then another 35 minutes gets
    us to 96 minutes have passed.
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    And that also gets
    us to 3:35, which
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    means we have 25
    minutes until 4:00.
Title:
Time word problem
Description:

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Video Language:
English
Team:
Khan Academy
Duration:
03:38
Fran Ontanaya edited English subtitles for Time word problem
Amara Bot edited English subtitles for Time word problem
Amara Bot edited English subtitles for Time word problem

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