Addition Class 3 Notes Maths

Addition can be visualized as 'putting together' or two or more quantities. The addition is taking two or more numbers and adding them together. The sign for Addition is + (plus). 

Let us start by studying Simple Addition First.

Simple Addition of 3-Digit Numbers (Without Carrying)

Example: 215 students from Delhi and 123 students from Chennai participated in a dance competition. How many students in all participated in the dance competition?

You need to add 215 and 123.

Thus, 338 students in all participated in the dance competition.

Addition of 3-Digit Numbers (With Carrying)

Example: Add 456 and 297.

Write the numbers in column form as shown.

Step 1: Add the ones. 
6 ones + 7 ones = 13 ones = 10 ones + 3 ones
= 1 ten 3 ones.
Write 3 under the ones column and carry over 1 to the tens column.
Step 2: Add the tens. 
5 tens + 9 tens + 1 ten (carried over) = 15 tens
= 10 tens + 5 tens = 1 hundred 5 tens. Write 5 under the tens column and carry over 1 to the hundreds column.
Step 3: Add the hundreds. 
4 hundreds + 2 hundreds + 1 hundred (carried over) = 7 hundreds
Write 7 under the hundreds column.
Thus, 456 + 297 = 753.

What are the Different Properties of Addition?

1. The Order Property of Addition

Changing the order of addends does not change the sum. This is known as the order property of addition.

• There are 2 students jumping rope. Then, 4 students join them.
  How many students are jumping rope in all?
  2 + 4 =
• If 4 students are jumping rope and 2 students join them.
  How many students are jumping rope in all?
  4 + 2 =

2. The Grouping Property of Addition

While adding three numbers, either the first two or the last two numbers may be grouped. Grouping the addends in any manner does not change the sum. This property is called the grouping property of addition.

• Aman caught 5 fish, Ravi caught 2 fish and Ankur caught 6 fish. How many fish did they catch altogether?
  The problem can be written as 5 + 2 + 6 =or in column form as shown below.
  
• You will have to find the sum of three numbers in two steps because you can add only two numbers at a time. One way to add is to begin at the top, add the first two numbers and then add their sum to the last number. 
• Another way to add is to begin at the bottom, add the last two numbers, and then add their sum to the first number.

• Begin at the top
  
• Begin at the bottom
  

3. Zero Property of Addition

The sum of any number and zero is the number itself. This is known as the zero property of addition.

Example: Aadhya put 6 books on the top shelf. She left the middle shelf empty. She put 3 books on the bottom shelf. How many books did she have on all the shelves?

In the language of mathematics, the problem can be written as 6 + 0 + 3 =  The number 0 shows not any books on the middle shelf. The statement can also be written in column form as shown. Notice that adding zero to a number does not change the value of the number.
 
Thus, there are 9 books in all on the shelf.

Simple Addition of 4-Digit Numbers (Without Carrying)

Example: Add 1432 and 6263.

Write the numbers in column form.

Step 1: Add the ones. 
2 ones + 3 ones = 5 ones
Write 5 under the ones column.
Step 2: Add the tens. 
3 tens + 6 tens = 9 tens
Write 9 under the tens column.
Step 3: Add the hundreds. 
4 hundreds + 2 hundreds = 6 hundreds
Write 6 under the hundreds column.
Step 4: Add the thousands. 
1 thousand + 6 thousands = 7 thousands
Write 7 under the thousands column.
Thus, 1432 + 6263 = 7695.

Addition of 4-Digit Numbers (With Carrying)

Example 1: Add 2468 and 5896.

Follow the same method as explained in the addition of 3-digit numbers. Look at the following steps.

Thus, 2468 + 5896 = 8364.

Example 2: Add 5846 and 2588.

Thus, 5846 + 2588 = 8434.

How to Add More Than Two Numbers?

Example 1: The number of students visiting a zoo on the first four days of the week are as shown in the table. How many students in all visited the zoo?

We add the number of students who visited the zoo on all four days as shown on the right.

Step 1: Add all the digits at the ones place.
6 + 9 + 2 + 5 = 22 ones = 20 O + 2 O = 2 T + 2 O
Carry 2 T to tens column.
Step 2: Add all the digits at the tens place.
2 (carried over) + 2 + 4 + 1 + 4 = 13 tens = 10 T + 3 T = 1 H + 3 T
Carry 1 H to hundreds column.
Step 3: Add all the digits at the hundreds place.
1 (carried over) + 1 + 3 + 5 + 2 = 12 hundreds = 10 H + 2 H = 1 Th + 2 H
Carry 1 Th to thousands place.
Step 4: Add all the digits at thousands place.
There is only 1 digit, which is 1.
Thus, the number of students who visited the zoo on the first four days is 1232.

Example 2: Add: 864 + 2907 + 3765 + 1874.

Thus, 864 + 2907 + 3765 + 1874 = 9410.

How to Check whether the Addition you did was Correct or Not?

• It is always a good practice to check your answer. 
• Regular practice becomes a habit and you would rarely make a mistake. 
• Let us learn how to check the answer with the help of the following example.

Example: Add 544 and 795.

Check:
There are two ways to check addition.

• You can check addition by adding up.
  
• You can also check addition by subtracting one of the addends from the sum. You will get the remaining addend.
  

Edurev Tips: You should be able to check your answer mentally by any of the two methods.

Problems Based on Real Life Situations

Example 12: The students had to sell the tickets for a play. In the first week, they sold 2,380 tickets and in the second week, they sold 3,150 tickets. How many total tickets did they sell in all?

Number of tickets sold in the first week = 2380
Number of tickets sold in the second week = 3150

Total number of tickets sold = 2380 + 3150 = 5530.