Operations

Addition

Addition is an operation used to calculate the total or sum of two or more numbers.

Addition combines two quantities into a single quantity.

Numbers that are added together are called addends, and the total is called the sum.

We can add 3-digit numbers in the same manner as we add 2-digit or single digit numbers.

Addition on Number Line

Addition is easy to understand on number line.

Step 1: First, place the first number on the number line.

Step 2: Express the second number in expanded from.

Step 3: Now, proceed through the number line according to the expanded form of the second number from the first number.

Step 4: The last point that we reach is the sum of the two numbers.

Example:Add 242 and 126 using number line.

Answer: 242 + 126 = 242 + 100 + 20 + 6

Hence,
242 + 126 = 368

Addition of 3-digit Numbers Without Carry Over

Step 1: Start adding digits from ones place.

Step 2: Add the digits at tens place.

Step 3:Add the digits at hundreds place.

Example:

Add: a) 356 + 443       b) 145 + 623 + 211

Answer:

a)

b)

Addition of 3-digit Numbers with Carry Over

Step 1: Start adding digits from ones place. If there is any carry-over, then add the number of the carry forward with the digits at tens place.

Step 2: Add the digits at tens place. If there is any carry-over, then add the number of the carry forward with the digits at hundreds place.

Step 3:Add the digits at the hundreds place.

Example:

Add: a) 356 + 465         b) 149 + 385 + 676

Answer:

a)

b)

Word Problems

Following are the steps to solve a word-problems involving addition

Step 1: Read the question carefully and identify the numbers to be added to get the total.

Step 2: Add the numbers to find the sum.

Step 3:One final sentence should be there at the end of the solution which concludes the result.

Example:

a) On the sports day of a school, 120 students participated in a 100-metre race, 164 students participated in the Spoon race, and 56 students participated in the sack race. How many students participated in all?

Answer:

The number of students who participated in the 100- metre race = 120
The number of students who participated in the Spoon Race = 164
The number of students who participated in the Sack Race = 56
The total number of students who participated in the Sports day events =

120 + 164 + 56 = 340

Hence, 340 students participated in all.

b) At a school picnic, there were 250 girls and 234 boys. How many students went to the picnic?

Answer:

The number of girls who went to the picnic = 250
The number of boys who went to the picnic = 234
So, the total number of students who went to the picnic is:

250 + 234 = 484

Hence, 484 students went to the picnic.