WEBVTT
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Complete the following pattern, something, something, eight, seven, six, five, four, three, two, one, and zero.
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In this problem, we’re given a pattern of numbers.
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And we’re asked to complete it by thinking of the first two numbers that happen at the start.
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What do the numbers sound like when we read them aloud?
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Eight, seven, six, five, they sound like a countdown.
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The sort of thing you hear when a rocket is about to take off.
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And that word can give us a clue as to what the pattern is doing.
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It’s counting down.
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Let’s draw a number line to see the direction that we’re counting.
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The first number that we know of in our pattern is eight.
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And from eight, we count to seven.
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This is a count of one backwards.
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From the number seven, we also then count one backwards to get to the number six.
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And then, five, four, three, two, one, and zero.
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This is a decreasing pattern, going down by one each time.
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So, what are the two numbers that come before eight?
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Well, we know if we’re counting backwards in ones, the number before eight is nine, nine, eight, seven, and so on.
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The first number in our pattern is a number that we will say before we count backwards to the number nine.
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The answer is 10, 10, nine, eight, and so on.
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And so our completed pattern is 10, nine, eight, seven, six, five, four, three, two, one, zero.