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Convert ten million centimeters into kilometers.
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Now centimeters and kilometers are both lengths in the metric measuring system.
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Now in that system, the basic measure of length is the meter, and then we have fractions of meters and we have multiples of meters.
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So to give you an idea of what a meter is, the average car height is about one point four one point five meters, so one meter is about two-thirds as tall as the average car.
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The word kilo means a thousand, so a kilometer or a “kee-lo-mee-ter” is a thousand meters, and the word centi means a hundredth of, so one centimeter is a hundredth of a meter; a hundred centimeters make up one meter.
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So if I start off with ten million centimeters, each group of a hundred centimeters is gonna make up one meter.
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That means there are a hundred times as many centimeters as there are meters.
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So I need to divide ten million by a hundred to work out how many meters this is equivalent to.
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Now that might look a bit weird because I said you take one meter and divide it by a hundred to get one centimeter, and then I said take the number of centimeters and again divide it by a hundred and that turns it into meters.
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Well both of those things are right.
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A centimeter is one hundredth of a meter, so if I take the number of centimeters, I would need to divide that by a hundred to get the number of meters, and likewise for meters in kilometers.
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A kilometer is made up of a thousand meters; it’s a thousand times as big as a meter.
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So if I have a measurement, there are gonna be a thousand times as many meters in that measurement as there are kilometers.
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And that means if I want to convert the number of meters into the number of kilometers, I’m gonna have to divide that number by a thousand.
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And that’s gonna give me one hundred kilometers.
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Let’s just work backwards and check that.
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If I’ve got one hundred kilometers, every one of those kilometers is a thousand meters, so in terms of meters it’s gonna be a thousand times a hundred, a hundred thousand meters.
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And each one of those meters is made up of a hundred centimeters, so there are gonna be a hundred times more centimeters than there are meters.
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So that’s gonna be a hundred times a hundred thousand centimeters, and that is ten million centimeters, which was what we were asked to do in the question.
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So looks like we’re right.