WEBVTT
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What is the length of each interval in the given line?
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First, we need to think about what an interval is.
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The space between each dash mark is the interval.
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To find the interval, we can find the difference between 960 and 949.
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To find the difference, we will use subtraction.
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We will subtract 949 from 960.
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I need to borrow one of the tens place.
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So now I can say 10 minus nine is one.
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Five minus four is one.
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Nine minus zero is zero.
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This tells me that there is a space of 11 between 949 and 960.
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Let’s check our answer by looking at another interval on the line.
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This time, we’ll go from 1004 to 1015.
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We want to know if we add 11 to 1004, will it equal 1015?
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It does!
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If you add 11 to 1004, it’s equal to 1015.
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This confirms that the interval of this line is 11.