Learn Addition

What is Addition?

Addition is a basic arithmetic operation that combines two or more numbers to find their total, called the sum. It is represented by the "+" symbol. For example, 2 + 3 = 5, where 5 is the sum.

Addition is used in everyday life, such as calculating the total cost of items, counting objects, or determining distances.

Types of Addition

• Single-digit addition: Adding numbers from 0 to 9 (e.g., 4 + 5).
• Two-digit addition: Adding numbers from 10 to 99, with or without carrying (e.g., 23 + 45).
• Three-digit addition: Adding numbers from 100 to 999, often involving carrying (e.g., 456 + 789).
• Four-digit addition: Adding numbers from 1000 to 9999, with multiple carries (e.g., 2345 + 6789).
• Addition with regrouping (carrying): When the sum of digits in a column exceeds 9, you carry over to the next column.
• Addition without regrouping: When no carrying is needed (e.g., 123 + 456).

Examples of Addition

1. Single-Digit Addition

6 + 3 = 9

Explanation: Add the numbers directly to get the sum.

2. Two-Digit Addition (Without Carrying)

23 + 45 = 68

Explanation: Align the numbers by place value:

   23
+ 45
-----
   68
                

3. Two-Digit Addition (With Carrying)

58 + 47 = 105

Explanation: Add ones: 8 + 7 = 15 (write 5, carry 1). Add tens: 5 + 4 + 1 = 10 (write 0, carry 1). Hundreds: 1 = 1.

   58
+ 47
-----
  105
                

4. Three-Digit Addition (With Carrying)

456 + 789 = 1245

Explanation: Add ones: 6 + 9 = 15 (write 5, carry 1). Tens: 5 + 8 + 1 = 14 (write 4, carry 1). Hundreds: 4 + 7 + 1 = 12.

   456
+ 789
------
 1245
                

5. Four-Digit Addition (With Carrying)

2345 + 6789 = 9134

Explanation: Add ones: 5 + 9 = 14 (write 4, carry 1). Tens: 4 + 8 + 1 = 13 (write 3, carry 1). Hundreds: 3 + 7 + 1 = 11 (write 1, carry 1). Thousands: 2 + 6 + 1 = 9.

  2345
+ 6789
------
  9134
                

Quiz

Test your addition skills with these 20 multiple-choice questions!

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