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Subtracting with Borrowing or Regrouping, a selection of answers from the Dr. Math archives.

Borrowing in Subtraction
When doing subtraction problems like 100-99, why do the zeros become nines? How does borrowing work?

Carrying and Borrowing
My son has a problem understanding addition and subtraction when he has to do regrouping, what I call carrying and borrowing...

Regrouping and Subtracting
37-9: Do you need to regroup? Subtract the ones. Subtract the tens. How many are left?

Regrouping Four 10's
How would you regroup four 10's to find the difference between 341 and 228?

Subtracting Fractions with Borrowing
When you are subtracting a fraction, do you always take one away from the whole number?

Subtracting Mixed Numbers
I don't really understand subtracting mixed numbers.

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Elementary Subtraction
Index of Selected Answers to Common Questions

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