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What is 10 more than 1,212?
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What is 10 less than 1,212?
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This question is all about how numbers change when we find 10 more or 10 less than them.
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And it’s the same number we’re starting from each time: 1,212.
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Now because we’re counting in tens here, finding 10 more or 10 less, we can use our knowledge of place value to help us because one of the digits in a four-digit number is worth tens.
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1,212 contains one 1,000, two 100s, one 10, and two ones.
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In the first part of our question, we’re asked to find 10 more than this number.
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Well, as we’ve just said, 1,212 contains one 10.
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And if we find 10 more than this number, we need to add one more 10.
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We’ve added another 10s block, and now we have two 10s.
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None of the other digits have changed.
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We still have one 1,000, two 100s, and two ones.
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But instead of one group of 10, we now have two.
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10 more than 1,212 is 1,222.
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Now let’s use the same idea, but this time we’re going to find 10 less than our number.
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So, just like before, we can start with 1,212.
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And which part of our number do you think is going to change if we need to find 10 less than this?
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Well with a question like this, we always need to start by looking at the tens digit.
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Our number contains one 10.
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So if we find 10 less than this, we’re going to need to take away this 10.
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Instead of one 10, we now have zero tens.
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Once again, the thousands digit, the hundreds digit, and the ones digit in our answer are exactly the same.
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They haven’t changed at all.
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However, because we have 10 less instead of one 10, we need to write a zero in the tens place.
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We’ve used our knowledge of place value to find 10 more and 10 less than the same number.
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10 more than 1,212 is 1,222, and 10 Less than 1,212 is 1,202.