Regrouping for Double-Digit Subtraction Two-Digit Subtraction – Regrouping.
Everyday Mathematics Partial-Differences Subtraction
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Everyday MathematicsPartial-Differences Subtraction
Partial-Differences SubtractionPartial-differences subtraction involves:Thinking about numbers in expanded notation;Using place value to determine partial differences; andAdding partial differences.
Everyday Mathematics
Partial-Differences SubtractionSolve: 471 293We begin by thinking about each number in expanded notation.471 = 400 + 70 + 1293 = 200 + 90 + 3We can subtract in any place-value order. Everyday Mathematics 471 293
Partial-Differences SubtractionSolve: 471 293Everyday Mathematics 471 293
Lets start with the hundreds place.471 = 400 + 70 + 1293 = 200 + 90 + 3
400 200 = 200
Partial-Differences SubtractionSolve: 471 293
Everyday Mathematics 471 293Now we subtract the tens.Since we are subtracting a larger400 200 = 200number from a smaller number, the difference is negative.
471 = 400 + 70 + 1293 = 200 + 90 + 3
70 90 = 20
Partial-Differences SubtractionSolve: 471 293
471 293
400 200 = 20070 90 = 20
Everyday MathematicsFinally, we subtract the ones. 471 = 400 + 70 + 1293 = 200 + 90 + 3Since we are subtracting a largernumber from a smaller number, the difference is negative. 1 3 = 2
Partial-Differences SubtractionSolve: 471 293Everyday Mathematics 471 293We add the partial-differences to find the total. 20020+ 2178
471 293 = 178
Partial-Differences SubtractionWhen children use partial-differences subtraction they practice
Everyday Mathematicsa variety of skills related to number sense and algebraic reasoning. For example:Thinking about numbers in expanded notation;Using place value to determine partial differences; andAdding positive and negative numbers.If children start with the largest place value, which is generally
their inclination, they begin the problem-solving process with a
reasonable estimate of what the final answer should be.