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Calculate negative three multiplied by seven multiplied by 10.
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As multiplication is commutative, we could multiply the numbers in any order.
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We could start by multiplying negative three by seven.
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Alternatively, we could multiply seven by 10.
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Our first step could also be multiplying negative three by 10.
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In this question, we’ll work from left to right and start by multiplying negative three by seven.
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In order to do this, we need to remember what happens when we multiply positive and negative numbers.
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Multiplying two positive numbers or two negative numbers gives us a positive answer.
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However, multiplying a positive number by a negative number in either order gives us a negative answer.
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If the signs are the same, our answer will be positive.
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Whereas if they are different, the answer will be negative.
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Three multiplied by seven is equal to 21.
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Therefore, negative three multiplied by seven is equal to negative 21.
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The answer is negative as we’re multiplying a negative number by a positive one.
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Our final step is to multiply negative 21 by 10.
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Multiplying any number by 10 moves all the digits one place to the left.
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So 21 multiplied by 10 is equal to 210.
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This means that negative 21 multiplied by 10 is equal to negative 210.
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The calculation negative three multiplied by seven multiplied by 10 is equal to negative 210.
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We get exactly the same answer if we multiply seven and 10 first.
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Seven multiplied by 10 is equal to 70.
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Multiplying this by negative three also gives us negative 210.