Column subtraction with regrouping
Name: _____________________ Date: __________
Show your thinking with numbers, words, or a drawing.
1. 56 − 49 = ?
2. 93 − 69 = ?
3. 94 − 45 = ?
4. 84 − 67 = ?
5. 75 − 66 = ?
Answer key · Column subtraction with regrouping
1. 7
Regroup wherever the top digit is smaller. 56 becomes 4 tens, 16 ones.
Subtract each column, starting with the ones: 16 − 9 = 7, 4 − 4 = 0.
56 − 49 = 7.
2. 24
Regroup wherever the top digit is smaller. 93 becomes 8 tens, 13 ones.
Subtract each column, starting with the ones: 13 − 9 = 4, 8 − 6 = 2.
93 − 69 = 24.
3. 49
Regroup wherever the top digit is smaller. 94 becomes 8 tens, 14 ones.
Subtract each column, starting with the ones: 14 − 5 = 9, 8 − 4 = 4.
94 − 45 = 49.
4. 17
Regroup wherever the top digit is smaller. 84 becomes 7 tens, 14 ones.
Subtract each column, starting with the ones: 14 − 7 = 7, 7 − 6 = 1.
84 − 67 = 17.
5. 9
Regroup wherever the top digit is smaller. 75 becomes 6 tens, 15 ones.
Subtract each column, starting with the ones: 15 − 6 = 9, 6 − 6 = 0.
75 − 66 = 9.
Try it together
Make a small group of blocks. Remove some and ask how many are left. Say and write the subtraction together, then put the blocks back to check.