WEBVTT
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20 percent of 3000 equals what.
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The word percent means out of 100.
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And it’s a way of showing parts of a whole, with 100 percent being the same as a whole.
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In our problem, the whole amount is 3000.
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And in this problem, we’re being asked to find what 20 percent of 3000 is worth.
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The interesting thing about problems like this is that there are often several ways we can find the answer.
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So how can we find 20 percent of a number?
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Let’s go through two different methods that we could use.
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The first is to find 10 percent of 3000 and then double it to give us 20 percent.
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Finding 10 percent of a number is usually quite quick to do, and so is doubling.
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So this is quite an efficient strategy we could use.
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There are 10 lots of 10 in 100.
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So to find 10 percent of a number, all we need to do is to divide that number by 10.
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And what is 3000 divided by 10?
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The digit shift one place to the right.
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And we get an answer of 300.
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So if 10 percent of 3000 equals 300, then 20 percent of 3000 must be worth twice this amount.
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300 doubled equals 600.
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And so we know 20 percent of 3000 equals 600.
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We did say there was more than one method we could use.
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So let’s go through a second strategy that we could use to find the answer.
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This strategy involves thinking about 20 percent.
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How many lots of 20 percent are there in 100?
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One, two, three, four, five.
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There are five lots of 20 in 100.
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And so another way of thinking about this is that 20 percent is one-fifth of 100.
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So to find 20 percent of 3000, we just need to find one-fifth of 3000 or divide 3000 by five.
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And if we look carefully at our first method, we know that dividing by 10 and then multiplying by two is the same as dividing by five.
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And that’s why both methods are going to give us the same answer.
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So how many fives are in 3000?
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Well here, we can use a multiplication fact to help us.
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We know that 30 divided by five equals six.
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3000 is 100 times larger than 30.
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So there must be 100 times as many fives in it.
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So the answer must be 600.
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As we discussed, percentage questions are always interesting because there’s usually more than one way we could find the answer.
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Here, we found the answer by first finding 10 percent and then doubling it.
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And the second strategy was to realise that there are five lots of 20 in 100.
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So all we had to do was to divide by five and find one-fifth.
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20 percent is the same as one-fifth.
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So 20 percent of 3000 equals 600.