WEBVTT
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Determine the elapsed time from 7:52 am to 6:47 pm.
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Our starting point is 7:52 am, 7:52 in the morning.
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And our ending point is 6:47 pm, to 6:47 in the evening.
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To find the elapsed time, we can break the time down into pieces that are easier to calculate.
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We’ll start by calculating how much time has elapsed between 7:52 am and 8:00 am.
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We know that there are 60 minutes per hour.
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We started at 52 minutes after 7:00.
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If we subtract 52 from 60, it will tell us the elapsed time.
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Eight minutes passed between 7:52 am and 8:00 am.
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From this point, let’s calculate elapsed hours instead of elapsed minutes.
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When one hour passes from 8:00 am, it’s 9:00 am.
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If another hour passes from 9:00 am it becomes 10:00 am, 10 in the morning.
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And another hour would make it 11:00 am.
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Another and it becomes 12:00.
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But there’s an important shift here.
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We’ve now moved over into the noontime.
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And that means one hour after 11:00 am is 12:00 pm.
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We add another hour and it’s one o’clock in the afternoon.
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It’s 1:00 pm.
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Another hour and it becomes 2:00 pm.
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Another hour and it’s 3:00 pm.
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Another hour becomes 4:00 pm, another hour 5:00 pm.
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One more hour and now it’s 6:00 pm.
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Now we need to think about how much time elapses between 6:00 pm and 6:47 pm.
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Another way to say 6:47 pm is to say 47 minutes after 6:00.
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And that helps us see that 47 minutes have passed between 6:00 and 6:47.
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To find the total elapsed time, we’ll need to add these values up.
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We can’t add hours and minutes.
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So we need to add all the hours together and then all the minutes together.
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If we add up all the one hours, there are 10 of them.
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There are 10 ones.
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10 hours had passed.
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Now we add eight minutes and 47 minutes.
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Eight plus seven is 15.
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Write the five, carry the one.
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One plus four is five.
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Eight plus 47 equals 55, for 55 minutes.
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When we put those two values together, we get 10 hours and 55 minutes.
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The total elapsed time from 7:52 am to 6:47 pm is 10 hours and 55 minutes.