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Calculate 75 plus 16 plus five.
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To add these together without using a calculator or even really without writing much down, we can use some properties of addition to help us.
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Do you notice that 75 and five both end in fives?
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I know that I could easily mentally add 75 and five together.
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So I wanna regroup this problem and group 75 and five together, add those first, and then add the 16.
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Why are we allowed to move this problem around like this?
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The associative property of addition tells us that when we’re dealing with addition, we can group our numbers in any way that we want.
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In our case, we can add 75 and five together, which equals 80, and then add 16 to 80, which equals 96.
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By moving around the five and the 16, we were able to solve this problem mentally, thanks to the associative property of addition.
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When we calculate 75 plus 16 plus five or if we move it around, either way, the final answer is 96.