Three-Digit Addition and Subtraction Flashcard

Regrouping in addition is the process of carrying over a value from one column to the next when the sum of a column exceeds 9.

Regrouping in subtraction is the process of borrowing from the next column when the top digit is smaller than the bottom digit.

$$1245$$

$$234$$

$$274$$

$$145$$

$$801$$

The sum of two three-digit numbers is found by adding their corresponding digits, starting from the rightmost column.

The difference is found by subtracting the digits of the second number from the first, starting from the rightmost column.

If a column exceeds 9, you carry over 1 to the next column on the left.