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Rounding to nearest 10 or 100: Addition, subtraction, and estimationEstimate to add multi-digit numbers: Addition, subtraction, and estimationStrategies for adding two and three-digit numbers: Addition, subtraction, and estimationAdding with regrouping within 1000: Addition, subtraction, and estimation

Estimate to subtract multi-digit numbers: Addition, subtraction, and estimationStrategies for subtracting two and three-digit numbers: Addition, subtraction, and estimationSubtracting with regrouping within 1000: Addition, subtraction, and estimationAddition and subtraction missing value problems: Addition, subtraction, and estimationAddition and subtraction word problems: Addition, subtraction, and estimation

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