Doubles (Grade 2)
Doubles means adding a number to itself. When you double a number, you get two times that number.
For example, double of 4 means 4 + 4 = 8. Knowing doubles helps you add quickly in your head.
What is Doubles (Grade 2) - Class 2 Maths (Addition)?
A double is what you get when you add a number to itself.
| Number | Double | Answer |
|---|---|---|
| 1 | 1 + 1 | 2 |
| 2 | 2 + 2 | 4 |
| 3 | 3 + 3 | 6 |
| 4 | 4 + 4 | 8 |
| 5 | 5 + 5 | 10 |
| 6 | 6 + 6 | 12 |
| 7 | 7 + 7 | 14 |
| 8 | 8 + 8 | 16 |
| 9 | 9 + 9 | 18 |
| 10 | 10 + 10 | 20 |
All doubles give even numbers.
Types and Properties
Types of double problems:
- Simple doubles: 6 + 6 = 12
- Near doubles (doubles + 1): 6 + 7 = 6 + 6 + 1 = 13
- Near doubles (doubles − 1): 6 + 5 = 6 + 6 − 1 = 11
Near doubles use a known double to solve a close addition quickly.
Solved Examples
Example 1: Simple Double
Question: What is double of 7?
Think:
- Double of 7 = 7 + 7 = 14
Answer: Double of 7 is 14.
Example 2: Near Double (Plus 1)
Question: What is 8 + 9?
Think:
- 8 + 9 is close to 8 + 8
- 8 + 8 = 16
- Add 1 more: 16 + 1 = 17
Answer: 8 + 9 = 17
Example 3: Word Problem — Eyes
Question: 5 children are sitting in a row. Each child has 2 eyes. How many eyes in all?
Think:
- This is double of 5
- 5 + 5 = 10
Answer: There are 10 eyes in all.
Example 4: Word Problem — Socks
Question: Aman has 6 pairs of socks. Each pair has 2 socks. How many socks in all?
Think:
- 6 pairs = double of 6
- 6 + 6 = 12
Answer: Aman has 12 socks in all.
Example 5: Double of a Two-Digit Number
Question: What is double of 15?
Think:
- 15 + 15
- Ones: 5 + 5 = 10 (write 0, carry 1)
- Tens: 1 + 1 + 1 = 3
Answer: Double of 15 = 30
Example 6: Near Double Word Problem
Question: Priya has 9 red beads and 10 blue beads. How many beads in all?
Think:
- 9 + 10 is close to 10 + 10 = 20
- 9 + 10 = 20 − 1 = 19
Answer: Priya has 19 beads in all.
Example 7: Find the Number from Its Double
Question: Double of a number is 16. What is the number?
Think:
- ___ + ___ = 16
- 16 ÷ 2 = 8
- Check: 8 + 8 = 16 ✓
Answer: The number is 8.
Key Points to Remember
- Double of a number = the number + the number.
- All doubles are even numbers.
- Near doubles help solve 6 + 7, 8 + 9 type problems quickly.
- Double of 10 = 20, double of 20 = 40.
- Knowing doubles makes mental addition faster.
Practice Problems
- What is double of 9?
- Solve using near doubles: 7 + 8
- Ria has 8 bangles on each hand. How many bangles in all?
- What is double of 12?
- Double of a number is 14. What is the number?
- Aditi has 6 red crayons and 7 blue crayons. Use near doubles to find the total.
Frequently Asked Questions
Q1. What are doubles in maths?
Doubles means adding a number to itself. For example, double of 5 is 5 + 5 = 10.
Q2. Why are all doubles even numbers?
When you add any number to itself, the answer is always even. For example, 3 + 3 = 6, 7 + 7 = 14. Even odd numbers give an even double.
Q3. What are near doubles?
Near doubles are addition problems where one number is 1 more or 1 less than the other, like 6 + 7. You use the known double (6 + 6 = 12) and add or subtract 1.
Q4. How do doubles help in quick addition?
If you remember that 8 + 8 = 16, you can quickly solve 8 + 9 = 17 (one more) or 8 + 7 = 15 (one less).
Q5. Is double the same as multiplying by 2?
Yes. Double of 6 = 6 + 6 = 12, and 6 × 2 = 12. Both give the same answer.
Q6. What is double of 0?
Double of 0 is 0 + 0 = 0.
Q7. How do I find the original number if I know the double?
Divide the double by 2. If the double is 18, the number is 18 ÷ 2 = 9.
Related Topics
- Doubles and Near Doubles
- Multiplication Table of 2
- Addition of 2-Digit Numbers
- Addition Without Carrying
- Addition With Carrying (Regrouping)
- Adding Three Numbers
- Addition Word Problems (Grade 2)
- Properties of Addition (Grade 2)
- Mental Addition and Subtraction
- Addition of 3-Digit Numbers (Grade 2)
- Missing Numbers in Addition and Subtraction
