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Is 4.99 metric tons equal to 4990000 grams?
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This is an example of what we call a closed question.
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The answer isn’t going to be a number.
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It’s either going to be yes or no.
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So it might seem like quite a simple question.
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We’ve only got two choices.
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But we need to base our decision on maths.
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And we need to think carefully about the facts that we already know that can help us.
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The question mentions two measurements.
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These are measurements of mass.
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We have 4.99 metric tons.
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And then, we also have 4990000 grams.
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Notice how these two units of measurement are different.
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To start with, we need to think about how many grams there are in a one metric ton.
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And then, we’ll use this fact to help.
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The first fact we know that will help us is that 1000 grams are the same as one kilogram.
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This is quite a common fact.
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The next fact is not so well known.
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1000 kilograms are the same as one metric ton.
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So if 1000 grams are the same as one kilogram and 1000 kilograms equal one metric ton, then one metric ton is the same as 1000 times 1000 grams.
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And a thousand thousands are one million.
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A thousand thousands are the same as one million.
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And so, one metric ton is the same as one million grams.
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We can use this fact now to help us solve the problem.
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Because there are one million grams in one metric ton, to convert metric tons into grams, we need to multiply by one million.
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Multiplying by a million is the same sort of idea as multiplying by a 10, 100, 1000, and so on.
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It involves the digit shifting to the left.
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Here’s the number of metric tons that we have: 4.99.
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Now, we may know how to multiply this number by 1000.
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We shift the digits three places to the left when we multiply by 1000.
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We’ve already said that one million is one thousand thousands.
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So instead of shifting these digits three places to the left, we need to shift them six places to the left.
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A good way of remembering this is that one million has six zeros.
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This gives us a clue as to how many times to shift those digits.
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Let’s move them six times.
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One, two, three.
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Now, we need to start putting zeros in as placeholders to show that we’re shifting the digits.
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Four, five, six.
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Let’s read the number of grams that are equal to 4.99 metric tons: 4990000.
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This is exactly the same as the measurement in the question.
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The two measurements are equal.
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So although this problem seemed like a simple yes/no question, we still had to work out the maths behind it in order for us to come to an answer.
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Is 4.99 metric tons equal to 4990000 grams?
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Yes, it is.