Addition is the operation of combining or joining together quantities to find the total amount. It is represented by the plus (+) symbol. Some key ways to perform addition include: 1) Counting all items being added together, such as counting 7 fish from 2 fish bowls containing 2 and 5 fish respectively. 2) Using a number line to visually jump from the first addend to the sum, such as jumping from 3 to 7 when adding 3 + 4. 3) The column or vertical method for adding multi-digit numbers, which involves carrying amounts over 10 to the next column, such as when adding 25 + 18 by carrying the 1 from 13 in the ones column.

1. ADDITION
Basic Concept of Addition
Addition is finding the total or sum of two or more numbers together. Let us look at an
example. Here we see two fish in first fish bowl and five fish in the second fish bowl. How
many fish are there together? Let’s count them. We are actually adding number two to
number five. That is two plus five which is equal to seven. The plus sign is the symbol that
denotes addition operation and the answer obtained is called the sum. Similarly, the sum
of three birds and six birds is three plus six which is equal to nine birds in all.
Addition Using a Number Line
We also can carry out addition using the number line to find the sum of three and four
using the number line. We start at three and jump four numbers to the right. What number
do we get? Yes, you are right we get the number seven which is the answer. Therefore, the
sum of three and four is seven.
Vertical Addition with Carrying
We are going to see how to add two two digit numbers together with the sum involves
carrying. To device, we are going to use the standard written method which we also call
the column method. The example question, we will use twenty five plus eighteen. We lay
out somewhere like this with the numbers line up in columns. We’ll start by adding the
units column and then we’ll add the tens column. So first we add the two numbers in the
units column five and eight. Five plus eight equals thirteen. However, we can’t put the two
digit numbers in that column. So what we’ll do is to split thirteen up in to one and three.
We write the three in units columns and we carry over the one over to the next column. So
what we’ll do is to split thirteen up in to one and three. We write the three in units
columns and we carry over the one over to the next column. We can’t write that one
straight in as there are other numbers in that column that we need to add. So we write a
little number one underneath to make sure we don’t forget it. Now we can move on to the
tens column. The numbers that are in tens columns are two and one, and two plus one
equals three. But we also need to remember the one we’ve carried over. Three plus that
one makes four. So that, the number we write in the answer box. So now we’ve added all
the numbers together we have an anwer twenty five plus eighteen equals forty three.