## Key Concepts

- Addition without regrouping.
- Sum
- Addition to regrouping in hundreds.
- Regroup
- Addition to regrouping in ones, tens, and hundreds.

**Introduction**

In this chapter, we will learn about the addition of numbers up to 10,000 and the terms used for addition.

### 3.1 Addition without Regrouping

Addition without regrouping is when the digits add up to a number that is 9 or less. Here, the answer can simply be written below each place value column.

Example: Find the sum of 2483 and 3512.

**Sol:**

** Step 1:** Add ones

**Step 2:** Add tens

**Step 3:** Add hundreds

** Step 4:** Add thousand

### 3.1.1 Sum:

The result obtained from the addition of two numbers is called the sum.

**Example: **

### 3.2 Addition with regrouping in hundreds.

When carrying out addition, regrouping is often used to carry a group of ten to the next place value column up.

**Example:** Find 1300 + 3900.

**Sol: **

**Step 1:** Add the hundreds

3 hundreds + 9 hundreds = 12 hundreds.

= 1 thousand 2 hundred

**Step 2:** Add the thousands

1 thousand + 3 thousand + 1 thousand = 5 thousand

The sum of 1300 and 3900 = 5200

### 3.2.1 Regroup:

Regrouping can be defined as the process of making groups of tens when carrying out operations for addition with two-digit numbers or larger.

**Example:**

### 3.3 Addition with regrouping in ones, tens, and hundreds.

When carrying out addition with regrouping is often to move a group of ones, tens and hundreds to the next place value column up.

**Example:** Find 1143 + 2159.

**Sol: Step 1:** Add the ones

3 ones + 9 ones = 12 ones

** Step 2:** Add the tens

1 tens + 4 tens, + 5 tens =10 tens

**Step 3:** Add the hundreds

1 hundred + 1 hundred + 1 hundred = 3 hundred.

**Step 4:** Add the thousands

1 thousand + 2 thousand = 3 thousand

The sum of 1143 + 2159 = 3302

## Exercise

- Find 4211 + 346.
- Find 5243 + 4354.
- Sam brought 200 cupcakes from the bear bakery. Jack went to the same bakery and bought 259 cupcakes. How many cupcakes did they buy together?
- Find 1621 + 2245.
- Find 97675 + 40854.
- Add 82788 + 21932.
- Find 64286 + 59991.
- Find the sum of 2613 and 2418.
- Find the sum of 8243 and 6554.
- In addition to 2415 and 1234, what will be the first step in addition?
- Find 6259 + 2641.
- Find 244 + 465.

### What we have learnt:

- Understood how to add two or more digits without regrouping and understand about the term sum.
- Understood how to add two or more digits with regrouping, i.e., carrying one digit to next place value column up in hundreds and understood about the term regrouping.
- Understood how to add two or more digits with regrouping place values as ones, tens, and hundreds.