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Relationship between Addition and Subtraction within 100.
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In this video, we’re going to learn about the relationship between addition and subtraction.
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Here we have 10 beads.
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One is green and nine are orange.
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We can use the three numbers one, nine, and 10 to make two addition facts and two subtraction facts.
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One plus nine equals 10 and nine plus one equals 10.
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These are addition facts.
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We can also make two subtraction facts.
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10 take away one is nine and 10 take away nine is one.
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We call addition and subtraction inverse operations.
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Inverse operations are operations which are opposite and undo each other.
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So we can add one and nine to make 10 and then take it apart by taking away one to make nine.
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We can use the inverse operation to help us check our calculations.
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In this example, we’re going to solve the problem using subtraction and then we’re going to use the inverse addition to help us check our answer.
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The question tells us that Sophia and Benjamin have been asked to solve 96 take away 45.
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Sofia solves it and gets an answer of 51.
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Benjamin solves it and gets an answer of 31.
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Who’s correct?
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Use the vertical column method to find out.
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So the question tells us to solve 96 take away 45.
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Using our vertical column method, first we subtract five from six, which leaves us with one, then we work out nine take away four, which is five.
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51 is the answer that Sophia gave.
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So Sophia is correct.
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Now we have to check our answer using the inverse operation.
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What number do you add to 45 to get 96?
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Now instead of subtracting, we need to add because addition and subtraction are inverse operations.
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We need to check if 45 add 51 equal 96.
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Five plus one is six and four plus five is nine.
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96 take away 45 is 51.
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45 plus 51 is 96.
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The number we had to add to 45 to get 96 is 51.
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In this video, we’ve learned that addition and subtraction are inverse operations and we can use the inverse to help us check our calculations.