Solved Exercises on Two Digit Addition with Regrouping Practice in Grade 2

Master two digit addition with regrouping practice: extensive drills for mastering addition with carrying through these 5 detailed exercises.

Solution: Exercises 1 to 3
1 Basic Regrouping Practice
Exercise 1
Add 28 + 17. Practice the regrouping process step by step.
Definition:

Two Digit Addition With Regrouping: Adding two-digit numbers where the sum of ones digits is 10 or more, requiring carrying.

Regrouping Method:
  1. Add the ones digits
  2. Check if regrouping is needed
  3. Carry the extra ten to the tens place
  4. Add the tens digits including the carry
  5. Write the final answer
Problem
28 + 17
Ones: 8 + 7
15
Carry: 1 ten
5 ones
Step 1: Add the ones digits

8 + 7 = 15

Step 2: Check if regrouping is needed

15 is more than 10, so regrouping is needed

Step 3: Write 5 in the ones place

Write 5 in the ones place

Step 4: Carry 1 ten to the tens place

Carry 1 ten to the tens column

Step 5: Add the tens digits including the carry

2 + 1 + 1 = 4

28 + 17 = 45
Final answer:

28 + 17 = 45

Applied rules:

• Regrouping: When ones sum to 10 or more, carry to tens place

• Carrying: Converting 10 ones to 1 ten

• Place Value Addition: Add digits with the same place value

2 Regrouping Drill Practice
Exercise 2
Practice regrouping with 46 + 28. Focus on each step of the process.
Definition:

Regrouping Drill: Repeated practice of the regrouping process to build fluency.

Problem
46 + 28
Ones: 6 + 8
14
Carry: 1 ten
4 ones
Step 1: Add the ones digits

6 + 8 = 14

Step 2: Check if regrouping is needed

14 is more than 10, so regrouping is needed

Step 3: Write 4 in the ones place

Write 4 in the ones place

Step 4: Carry 1 ten to the tens place

Carry 1 ten to the tens column

Step 5: Add the tens digits including the carry

4 + 2 + 1 = 7

46 + 28 = 74
Final answer:

46 + 28 = 74

Applied rules:

• Regrouping: When ones sum to 10 or more, carry to tens place

• Carrying: Converting 10 ones to 1 ten

• Place Value Addition: Add digits with the same place value

3 Regrouping Workout Practice
Exercise 3
Strengthen your regrouping skills with 57 + 36. Show all steps clearly.
Definition:

Regrouping Workout: Intensive practice designed to strengthen regrouping skills.

Problem
57 + 36
Ones: 7 + 6
13
Carry: 1 ten
3 ones
Step 1: Add the ones digits

7 + 6 = 13

Step 2: Check if regrouping is needed

13 is more than 10, so regrouping is needed

Step 3: Write 3 in the ones place

Write 3 in the ones place

Step 4: Carry 1 ten to the tens place

Carry 1 ten to the tens column

Step 5: Add the tens digits including the carry

5 + 3 + 1 = 9

57 + 36 = 93
Final answer:

57 + 36 = 93

Applied rules:

• Regrouping: When ones sum to 10 or more, carry to tens place

• Carrying: Converting 10 ones to 1 ten

• Place Value Addition: Add digits with the same place value

Rules and methods, laws,...
28 + 17 = 45 (regrouping needed)
Regrouping Addition
Rule 1
Regrouping
Ones sum ≥ 10
Rule 2
Carrying
10 ones = 1 ten
Rule 3
Place Value
Add same place values
Key definitions:

Two Digit Addition With Regrouping: Adding numbers with two digits where the sum of ones digits is 10 or more

Regrouping: Converting 10 ones to 1 ten when the sum of ones is 10 or more

Carrying: Moving the extra ten from the ones place to the tens place

Place Value: The value of a digit based on its position in a number

Complete methodology:
  1. Add the ones digits: Calculate the sum of the ones
  2. Check if regrouping is needed: See if the ones sum is 10 or more
  3. Carry if needed: Move extra tens to the tens column
  4. Add the tens digits: Include any carried tens
  5. Write the final answer: Combine tens and ones
Tip 1: Always add the ones digits first to determine if regrouping is needed.
Tip 2: When regrouping, remember that 10 ones become 1 ten.
Tip 3: Circle or highlight the number you're carrying to avoid forgetting it.
Tip 4: Practice regularly to build fluency and confidence.
Common errors: Forgetting to carry when regrouping is needed, miscounting tens and ones, adding tens and ones together before completing operations.
Key strategies: Practice identifying when regrouping is needed, visualize with manipulatives, check answers by estimation.
Regrouping rules:

• When adding ones digits: if sum ≥ 10, regroup by carrying to tens place

• 10 ones = 1 ten (the basic principle of regrouping)

• Always add digits with the same place value

• For visual models, circle groups of 10 to show regrouping

Solution: Exercises 4 to 5
4 Speed Regrouping Practice
Exercise 4
Practice speed regrouping with 39 + 45. Focus on accuracy while working quickly.
Definition:

Speed Regrouping: Practice designed to build fluency and speed while maintaining accuracy.

Problem
39 + 45
Ones: 9 + 5
14
Carry: 1 ten
4 ones
Step 1: Add the ones digits

9 + 5 = 14

Step 2: Check if regrouping is needed

14 is more than 10, so regrouping is needed

Step 3: Write 4 in the ones place

Write 4 in the ones place

Step 4: Carry 1 ten to the tens place

Carry 1 ten to the tens column

Step 5: Add the tens digits including the carry

3 + 4 + 1 = 8

39 + 45 = 84
Final answer:

39 + 45 = 84

Applied rules:

• Regrouping: When ones sum to 10 or more, carry to tens place

• Carrying: Converting 10 ones to 1 ten

• Place Value Addition: Add digits with the same place value

5 Challenge Regrouping Practice
Exercise 5
Complete the challenge problem: 68 + 27. Show your work and verify your answer.
Definition:

Challenge Regrouping: More difficult problems to test mastery of regrouping skills.

Problem
68 + 27
Ones: 8 + 7
15
Carry: 1 ten
5 ones
Step 1: Add the ones digits

8 + 7 = 15

Step 2: Check if regrouping is needed

15 is more than 10, so regrouping is needed

Step 3: Write 5 in the ones place

Write 5 in the ones place

Step 4: Carry 1 ten to the tens place

Carry 1 ten to the tens column

Step 5: Add the tens digits including the carry

6 + 2 + 1 = 9

Step 6: Write the final answer

9 tens and 5 ones = 95

68 + 27 = 95
Final answer:

68 + 27 = 95

Applied rules:

• Regrouping: When ones sum to 10 or more, carry to tens place

• Carrying: Converting 10 ones to 1 ten

• Place Value Addition: Add digits with the same place value

Two Digit Addition with Regrouping Practice Concepts
46 + 28 = 74 (regrouping needed)
Regrouping Addition
Key definitions:

Two Digit Addition With Regrouping: Adding numbers with two digits where the sum of ones digits is 10 or more

Regrouping: Converting 10 ones to 1 ten when the sum of ones is 10 or more

Carrying: Moving the extra ten from the ones place to the tens place

Place Value: The value of a digit based on its position in a number

Complete methodology:
  1. Add the ones digits: Calculate the sum of the ones
  2. Check if regrouping is needed: See if the ones sum is 10 or more
  3. Carry if needed: Move extra tens to the tens column
  4. Add the tens digits: Include any carried tens
  5. Write the final answer: Combine tens and ones
Tip 1: Always add the ones digits first to determine if regrouping is needed
Tip 2: When regrouping, remember that 10 ones become 1 ten
Tip 3: Circle or highlight the number you're carrying to avoid forgetting it
Tip 4: Practice regularly to build fluency and confidence
Common errors: Forgetting to carry when regrouping is needed, miscounting tens and ones, adding tens and ones together before completing operations.
Success habits: Regular practice with regrouping activities, visualizing with manipulatives, checking answers by estimation.
Regrouping practice strategies:

• When adding ones digits: if sum ≥ 10, regroup by carrying to tens place

• 10 ones = 1 ten (the basic principle of regrouping)

• Always add digits with the same place value

• Practice with various examples to build fluency

• Check your answers by estimation or reverse operations

Two Digit Addition with Regrouping Practice Workflow

🔢
Step-by-Step Process
1
Add ones
2
Check regrouping
3
Carry tens
4
Add tens
5
Write answer
Regrouping Visualization
When ones digits sum to 10 or more, we convert 10 ones to 1 ten and carry it to the tens place.
Master Regrouping Practice for Math Success!

Questions & Answers

Question: How do I know if I need to regroup in two digit addition?

Answer: You need to regroup when the ones digits add up to 10 or more:

  • Add only the ones digits: Look at just the ones place of each number
  • Check the sum: If the ones digits add up to 9 or less, NO regrouping is needed
  • Check the sum: If the ones digits add up to 10 or more, YES regrouping is needed

For example: 28 + 13 → ones are 8 + 3 = 11 (regrouping needed)
But: 24 + 13 → ones are 4 + 3 = 7 (no regrouping needed)

Always check this BEFORE you start adding the tens!

Question: How much practice should my child do with regrouping?

Answer: Consistent daily practice is key for mastering regrouping:

  • Duration: 10-15 minutes per day of focused practice
  • Variety: Mix of basic problems, word problems, and visual models
  • Progression: Start with easier problems and gradually increase difficulty
  • Review: Regularly revisit previously learned concepts

Quality is more important than quantity - make sure your child understands each step before moving to the next problem.

Watch for signs of fatigue or frustration and take breaks when needed!

Question: What happens if I forget to carry the ten when regrouping?

Answer: If you forget to carry the ten when regrouping, you'll get the wrong answer! Here's why:

For example, in 39 + 45:
Correct way: 9 + 5 = 14 (write 4, carry 1), then 3 + 4 + 1 = 8, so answer is 84
Wrong way: 9 + 5 = 14 (write 4, forget to carry), then 3 + 4 = 7, so answer would be 74

The correct answer is 84, but if you forget to carry, you get 74, which is 10 less than the correct answer!

That's why it's important to circle or highlight the number you're carrying so you don't forget to add it!