Addition of 2-Digit Numbers
Addition of 2-digit numbers is one of the most important skills in Class 2 Maths. It means adding two numbers that each have a tens digit and a ones digit.
To add 2-digit numbers, we line them up in a column — ones under ones and tens under tens. Then we add each column from right to left (ones first, then tens).
Sometimes the ones column adds up to more than 9. When that happens, we carry (regroup) to the tens column.
What is Addition of 2-Digit Numbers - Class 2 Maths (Addition (Grade 2))?
Addition of 2-digit numbers means finding the total (sum) of two numbers between 10 and 99.
Column method:
| Tens | Ones | |
|---|---|---|
| First number | 3 | 4 |
| + Second number | 2 | 5 |
| Sum | 5 | 9 |
34 + 25 = 59
Addition of 2-Digit Numbers Formula
Step 1: Add the ones. Step 2: Add the tens. (Carry if ones sum ≥ 10)
Solved Examples
Example 1: Example 1: Add 23 + 14 (no carrying)
Question: Add 23 + 14.
Think:
- Ones: 3 + 4 = 7
- Tens: 2 + 1 = 3
Answer: 23 + 14 = 37.
Example 2: Example 2: Add 45 + 38 (with carrying)
Question: Add 45 + 38.
Think:
- Ones: 5 + 8 = 13 → write 3 in ones, carry 1 to tens
- Tens: 4 + 3 + 1 (carry) = 8
Answer: 45 + 38 = 83.
Example 3: Example 3: Ria’s books
Question: Ria has 32 story books and 26 colouring books. How many books does she have in all?
Think:
- We need to ADD: 32 + 26
- Ones: 2 + 6 = 8
- Tens: 3 + 2 = 5
Answer: Ria has 58 books in all.
Example 4: Example 4: Add 56 + 27
Question: Find 56 + 27.
Think:
- Ones: 6 + 7 = 13 → write 3, carry 1
- Tens: 5 + 2 + 1 = 8
Answer: 56 + 27 = 83.
Example 5: Example 5: Add 60 + 30
Question: Add 60 + 30.
Think:
- Ones: 0 + 0 = 0
- Tens: 6 + 3 = 9
Answer: 60 + 30 = 90.
Example 6: Example 6: Aman’s cricket runs
Question: Aman scored 47 runs in the first match and 36 runs in the second match. What is his total?
Think:
- 47 + 36
- Ones: 7 + 6 = 13 → write 3, carry 1
- Tens: 4 + 3 + 1 = 8
Answer: Aman scored 83 runs in total.
Example 7: Example 7: Add 18 + 75
Question: Find 18 + 75.
Think:
- Ones: 8 + 5 = 13 → write 3, carry 1
- Tens: 1 + 7 + 1 = 9
Answer: 18 + 75 = 93.
Key Points to Remember
- Line up numbers in columns: ones under ones, tens under tens.
- Always add from right to left (ones column first).
- If the ones column adds to 10 or more, carry 1 to the tens column.
- The sum of two 2-digit numbers can be a 2-digit or 3-digit number.
- Check your answer by reversing the numbers: 23 + 14 should equal 14 + 23.
Practice Problems
- Add 42 + 35.
- Find the sum: 28 + 54.
- Priya has 37 red beads and 46 blue beads. How many beads in all?
- Add 19 + 63.
- What is 50 + 48?
- Dev has ₹45 and gets ₹38 more. How much money does he have now?
Frequently Asked Questions
Q1. What is addition of 2-digit numbers?
It is finding the total when two numbers between 10 and 99 are combined. You add ones first, then tens, carrying if needed.
Q2. When do I need to carry in addition?
You carry when the ones column adds up to 10 or more. You write the ones digit of the sum and carry 1 to the tens column.
Q3. Can the sum of two 2-digit numbers be more than 99?
Yes. For example, 85 + 67 = 152. When the sum exceeds 99, you get a 3-digit number.
Q4. Why do we add ones before tens?
Because if the ones column adds to more than 9, you need to carry 1 ten to the tens column. If you add tens first, you miss the carry.
Q5. What if I add the numbers in any order?
The answer stays the same. 34 + 25 = 25 + 34 = 59. This is called the commutative property of addition.
Q6. How do I check my addition answer?
Subtract one of the numbers from the answer. If 34 + 25 = 59, then 59 − 25 should give 34. If it does, your answer is correct.
