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.