Using Place Value to Subtract (Regrouping)
Do you want to learn faster and more easily?
Basics on the topic Using Place Value to Subtract (Regrouping)
Using Place Value to Subtract – Introduction
We're diving into the world of using place value to subtract with regrouping. This method is essential for understanding how to handle subtraction when the top number is smaller than the bottom number in any place value. Let's get our paper and pencils ready because today, we're going to practise this together!
What Is Place Value Subtraction?
Place value subtraction involves breaking down numbers into tens and ones, then subtracting them. If the top number in any place value is too small, we regroup by borrowing from the next place value.
Here are the steps to tackle subtraction using place value:
| Step # | Action |
|---|---|
| 1 | Represent the first number with tens rods and ones cubes. |
| 2 | Subtract the second number starting with the ones place. |
| 3 | If there aren't enough ones, regroup by borrowing from the tens place. |
| 4 | Subtract the tens place. |
| 5 | Count how many tens and ones are left to find the answer. |
| 6 | Check your answer to ensure it makes sense with the problem. |
Let's practise understanding place value subtraction with a few examples.
Solving Place Value Subtraction Problems – Example
Example 1:
Mr. Squeaks needs to subtract 30 - 16.
Steps to Solve the Problem:
| Step # | Action | Pictorial Representation |
|---|---|---|
| 1 | Represent the first number (30) with tens and ones: 3 tens and 0 ones. |  |
| 2 | Subtract the ones place: 0 - 6. |  |
| 3 | Regroup by borrowing one ten and converting it to ten ones. Now we have 2 tens and 10 ones. |
 |
| 4 | Subtract the ones place again: 10 - 6 = 4. |  |
| 5 | Subtract the tens place: 2 - 1 = 1. |
 |
| 6 | Combine to get the answer: 1 ten and 4 ones = 14. |  |
Mr. Squeaks has 14 marbles left.
Example 2:
Mr. Squeaks needs to subtract 35 - 27.
Steps to Solve the Problem:
| Step # | Action |
|---|---|
| 1 | Represent the first number (35) with tens and ones: 3 tens and 5 ones. |
| 2 | Subtract the ones place: 5 - 7. |
| 3 | Regroup by borrowing one ten and converting it to ten ones. Now we have 2 tens and 15 ones. |
| 4 | Subtract the ones place again: 15 - 7 = 8. |
| 5 | Subtract the tens place: 2 - 2 = 0. |
| 6 | Combine to get the answer: 0 tens and 8 ones = 8. |
Mr. Squeaks has 8 marbles left.
Solving Place Value Subtraction Problems – Practice
Now, let's put your skills to the test. Solve these problems on your own, and check the solutions when you're ready!
Solving Place Value Subtraction Problems – Summary
Key Learnings from this Text:
- Solving problems using place value with regrouping can be achieved by following these steps:
| Step # | Action |
|---|---|
| 1 | Represent the first number with tens rods and ones cubes. |
| 2 | Subtract the second number starting with the ones place. |
| 3 | If there aren't enough ones, regroup by borrowing from the tens place. |
| 4 | Subtract the tens place. |
| 5 | Count how many tens and ones are left to find the answer. |
| 6 | Check your answer to ensure it makes sense with the problem. |
- Mastering place value subtraction with regrouping is an important foundational maths skill.
Keep practising these steps, and you'll become a pro at subtracting numbers using place value! Check out more fun maths challenges and exercises on our website to continue sharpening your skills.
Solving Place Value Subtraction Problems – Frequently Asked Questions
Transcript Using Place Value to Subtract (Regrouping)
"Look, Imani! We can use these as furniture!" "Those are marbles, used in a game." "Oh, then, teach me how to play, please!" Let's learn about using place value to subtract (regrouping) to help Mr. Squeaks win the game. There are many strategies to help with subtraction. One of them is using a place value chart. Remember, place value is the value of a digit depending on its place in a number. When using place value to subtract always start by representing, or showing the first number with base ten blocks. Then, subtract the second number starting with the ones place but, what happens if there aren't enough ones to subtract from? You can regroup, or borrow from another place value. We can take a ten from the tens place and move it to the ones place. To do this we must cross off one ten then move it to the ones place and show it by drawing ten ones. Now we have fourteen ones, and enough to subtract the second number! After this, subtract the second number from the first. Finally, count how many tens and ones are left in the place value chart to find the answer! Now that we have learnt a bit about place value with regrouping, let's help Mr. Squeaks! While playing, he needs to subtract thirty minus sixteen. Remember, start by representing the first number on the place value chart. We can represent thirty, with three tens and zero ones. Next, subtract the second number from the first by crossing out ones. We have zero ones and need to subtract six, which means we need to regroup! We can do this by crossing out a ten and drawing ten ones in the ones place. Now we can subtract six! After this we need to subtract one ten. Finally, we can count how many are left to find our answer! How many marbles did Mr. Squeaks have left? He had fourteen marbles! Mr. Squeaks wants to play again, and this time he needs to subtract thirty-five minus twenty-seven. Always start by representing, or, showing the first number with base ten blocks. Thirty-five has three tens and five ones. Next, subtract the second number from the first by crossing out ones. We need to subtract the seven in twenty-seven from the five in thirty-five, but there aren't enough ones so we must regroup! We need to take one ten from the tens place and move it to the ones place! Now we can take away seven. After that, we can subtract the two from the tens place. Finally, we can count how many are left to find our answer! How many marbles did Mr. Squeaks have left? He had eight marbles! Before we see if Mr. Squeaks won, let's review. Remember, when using place value to subtract with regrouping start by representing, or showing the first number with base ten blocks. Next, subtract the second number by regrouping a ten to the ones place and subtracting the ones. Then, subtract the tens. Finally, count how many are left to find our answer! And, Mr. Squeaks? Well, he might need help from Imani's beam to get the marbles home.
Using Place Value to Subtract (Regrouping) exercise
-
When do you use regrouping to solve subtraction problems?
HintsYou do not need to regroup if you have too many or just enough ones in the ones place to subtract the second number.
Regrouping moves a ten into the ones place to give you more ones in order to subtract the second number.
SolutionIt is helpful to regroup if there are not enough ones to subtract the second number.
Regrouping allows you to break a ten into the ones place, so you can then subtract the second number from the ones place.
-
Solve the subtraction problem using regrouping.
HintsStart by regrouping a ten and moving it into the ones place.
Subtract the 9 from the ones place.
Count the remaining tens and ones.
Solution48 - 9 = 39
After regrouping, you can subtract the 9 from the ones and you are left with 9 ones and 3 tens. This makes the number 39.
-
Which place value chart shows the subtraction problem 63 - 17?
HintsTo solve this problem, a ten needs to be regrouped to the ones place. This is shown by a ten rod being faded.
The problem is 63 - 17. We need to find a chart where 17 has been taken away after a ten has been regrouped.
17 is made up of 1 ten and 7 ones, so we need to find a chart where 1 ten and 7 ones has been subtracted (crossed out).
SolutionThis chart represents 63 - 17.
To begin with, there were 6 tens and 3 ones. Then, 1 ten was regrouped to the ones place. Next, 7 ones were taken away and 1 ten was taken away. This left us with 46 or 4 tens and 6 ones.
-
Find the solution to the subtraction problems using regrouping.
HintsHave a go at drawing your own place value chart, representing the tens with lines and the ones with dots.
If there are not enough ones to subtract the second number, regroup a tens rod into the ones place.
After you have subtracted the ones, subtract the tens.
To solve 53 - 27, start by making a place value chart of the number 53 and regrouping a ten into the ones place. You can then subtract 7 ones and 2 tens to find the solution.
To solve 46 - 8, start by making a place value chart of the number 46 and regrouping a ten into the ones place. You can then subtract the 8 ones to find the solution.
Solution- 53 - 27 = 26
- 46 - 8 = 38
-
Find the solution to the subtraction problem using regrouping.
HintsA ten has been regrouped to the ones place. We can now subtract 5 ones from the ones place.
Subtract five from the ones place.
Subtract two tens and count the remaining tens rods and ones cubes to find the answer.
Solution63 - 25 = 38
When you regroup a ten into the ones place, you can then subtract 5 from the ones place and 2 from the tens place. You are left with 38.
-
Solve the subtraction problems using regrouping.
HintsDraw your own place value tables using lines to represent the tens and dots to represent the ones.
You will need to regroup a ten to the ones place to solve each of these problems.
Once you have regrouped, subtract the ones and the tens to find the answer.
Solution- 81 - 49 = 32
- 76 - 28 = 48
- 95 - 66 = 29
- 52 - 17 = 35
Subtract by Adding
Subtraction (Counting on) — Let's Practise!
Using Base 10 Blocks to Subtract 2 Digit Numbers
Subtraction - Adjusting Numbers
Using Place Value to Subtract Two Digit Numbers (No Regrouping)
Using Place Value to Subtract Two Digit Numbers (No Regrouping)—Let's Practise
Using Base Ten Blocks to Subtract Two Digit Numbers (With regrouping)
Using Place Value to Subtract (Regrouping)
