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Miranda needs to add 68 + 19 mentally but is struggling. If she knows that 68 + 20 = 88, how can she use this to help?

User Tony Ruth
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1 Answer

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She can use 68 + 20 = 88 to help by noticing that the 20 is ahead of 19 by 1. She can easily mentally turn the 20 into a 19 and realized that the 88 would become 87.
User Fazal Haroon
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