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Is the calculation two multiplied by four multiplied by 629 equals 5012 correct?
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The answer to this problem is either yes or no.
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Either two times four times 629 does equal 5012 or doesn’t.
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To find out which one is true, we’re going to have to calculate the answer for ourselves.
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To find the answer, we need to multiply three numbers together.
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The first two numbers in the multiplication are single-digit numbers.
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They’re easy to deal with.
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But then, we have a three-digit number.
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So to find the answer, we’re gonna have to give this a little bit of thought.
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The first thing we can do is to make the multiplication simpler.
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Two times four equals eight.
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And so, two times four times 629 is exactly the same as eight times 629.
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One thing we know about multiplications, which is the same as additions, is that we can multiply in any order and the answer will always be the same.
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And so, we could swap the two numbers that we’ve got in our multiplication and rewrite it as 629 multiplied by eight.
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It makes no difference to the answer, but it might help us to have the larger number first.
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There are several different ways we could multiply 629 by eight.
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Multiplying by eight is the same as doubling, then doubling, then doubling again.
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So we could double 629, then double it, and then double it a third time.
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Another method we could use is short multiplication.
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Let’s use this method to find the answer.
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Is it going to be the same as 5012?
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We can begin by multiplying our ones digit by eight.
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What is nine times eight?
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Well, we know that 10 eights are 80.
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So nine eights must be eight less than 80.
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80 take away eight equals 72, which is the same as seven tens and two ones.
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Next, we need to multiply our tens digit.
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Two tens multiplied by eight equals 16 tens.
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But we already have seven tens underneath.
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So that takes us to 23 tens or 230.
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Let’s pause the calculation for a moment.
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We’ve solved the problem.
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Can you see why?
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Look at the tens digit in our answer, and then compare it with the tens digit in 5012.
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We’ve calculated that the number is going to have three tens in it.
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But 5012 only contains one ten.
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So we can see that two times four times 629 is not going to equal 5012.
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It’s not correct.
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Well, we’ve only got one more digit to multiply, and it would be a shame to stop there.
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So, let’s continue and to find the actual answer.
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Six hundreds multiplied by eight equals 48 hundreds.
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We’ve also got two hundreds underneath, so that takes us to 50 hundreds or five thousands.
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The actual answer to the calculation two times four times 629 is 5032.
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As soon as we got to the tens digit, we could see that the calculation was not correct.
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And so as our answer, we just need to give the word no.
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The calculation in the problem is not correct.