- Counting things together is called addition.
- The words total, sum, add, more, in all, altogether etc., mean addition.
- The symbol for addition is +, read as plus.
- The numbers that are added are called addends.
- The answer we get by adding two numbers is called sum.
Note: The sum of two numbers is more than each of the numbers.
A line with numbers at equal places on it is called a number line.
- We can add numbers using a number line. e.g., 3 + 4
Adding numbers by writing them in a line (across) is called horizontal addition, e.g., 5 + 3 = 8 (
- We can also use our fingers, draw lines and count objects to add numbers.
- Adding numbers by writing them one below the other (down) is called vertical addition.
- Addition using Ones: Add the numbers and write the sum.
e.g., (a) (b)
- Addition using Tens and Ones: Add the ones first, write the sum and then add the tens.
Note: Add ones first and then add tens.
Adding 0 to a number gives the same number as the sum. e.g., 6 + 0 = 6