Subtracting Three-Digit Numbers with Regrouping

The video tutorial explains a subtraction problem involving 629 and 172. It begins by breaking down the numbers into hundreds, tens, and ones. The tutorial highlights the challenge of subtracting a larger number from a smaller one in the tens place and introduces the concept of regrouping or borrowing to solve this issue. By taking 100 from the hundreds place and adding it to the tens place, the problem is resolved, allowing for straightforward subtraction. The video concludes with the final subtraction steps, resulting in the answer 457.

What is the expanded form of 629?

• 600 + 20 + 9

• 600 + 30 + 9

• 600 + 29

• 620 + 9

What is the expanded form of 172?

• 1 + 72

• 170 + 2

• 100 + 70 + 2

• 100 + 72

What is the result of 9 minus 2?

• 7

• 6

• 5

• 8

Why can't we subtract 7 from 2 directly?

• Because they are in different places

• Because 2 is larger than 7

• Because 7 is larger than 2

• Because subtraction is not possible

What is another term for regrouping?

• Multiplying

• Borrowing

• Dividing

• Adding

What do we do to the hundreds place when we regroup?

• Subtract 50 from it

• Leave it unchanged

• Add 100 to it

• Take 100 from it

What does the 12 in the tens place represent after regrouping?

• 12 tens

• 12

• 1.2

• 120

What is the result of 12 tens minus 7 tens?

• 4 tens

• 3 tens

• 5 tens

• 6 tens

What is the result of 500 minus 100?

• 200

• 100

• 300

• 400

What is the final result of the subtraction 629 - 172?

• 457

• 467

• 447

• 437