Understand Negative Numbers and their Operations

Children, Earlier we have studied about 3 digit subtraction with regrouping and today i am going to tell you the most simplest and a bit complex topic- Numbers which comes under Gujarat Board Syllabus. When we start studying math we will first introduced with number. Numbers can be positive or negative.  Positive numbers are 1, 2, 3, 4, 5, and so on. Positive sign (+) or no sign means the number is positive. A grade IV student is aware of zero’s concept and can solve math problems related to it, Whole numbers starts with 0, 1, 2, 3, 4, 5, and so on. Numbers lesser than zero (0) are called negative numbers. A negative sign (-) implies that the number is negative. Negative numbers are -5, -4, -3, -2, -1, and so on.
In case of negative numbers -5 is less then -4 and so as -4 is less then -3.
It is always easy for a grade IV student to perform some operation on positive numbers. Because it is easy to add, subtract, multiply or divide them. But in case of negative numbers those operations causes some problems for them. Because of the negative sign attached with them and it is always important to take extra care of them. Because while performing operations if we unknowingly change the sign than the complete answer is wrong.(want to Learn more about Negative Numbers ,click here),

Now we will discuss operations that can be performed on negative numbers.

Addition:
Adding a negative number is not easy as adding a positive number. While we add positive number we simply plus them for example: 5 + 6 = 10 but in case of negative numbers we couldn’t do this thing.
Let’s take an example to understand this:
Add 5 to -3.
We can do this by just putting + sign between them. It is good practice to use parentheses  That is
5 + (-3) = 2
Suppose if we -5 + 3 then. This time our answer we be changed. Now we have answer -2 instead of 2.

Subtraction:
When we perform subtraction operations the sign of the number after the operation sign (-) gets changed.
Example:
            Subtract 3 from 6.
                        +6 – (+3)
Now the sign of +3 will be changed into – sign. Se the answer will be positive 3.
Now suppose we have -6 and +3 and then the result will be
                        (-6) – (+3)
                        -6 -3 = -9


Multiplication:
While multiplying negative numbers we need to always remember few points:

1. If negative numbers are even in sign then the result will be a positive number.
2. If negative numbers are odd in sign then the result will be a negative number.

Example:
            -3 x -4 = 12
            -5 x  2 = -10

Division:
Similarly like multiplication we need to remember some issues while performing division operation. There are four points listed below:

1. If we divide positive number from a positive number result will be positive.

                  Example: 6/2 = 3

2. If we divide negative number from a positive number result will be negative.

                  Example: -8/4 = -2

3. If we divide positive number from a negative number result will be negative.

                  Example: 12/-3 = -6

4. If we divide negative number from a negative number result will be positive.

                        Example: -25/-5 = 3


Now you all are aware of the concept of negative numbers and their operations. Do practice this with interest and I am very much sure you will find it very easy and if anyone want to know about Properties of odd/even numbers then they can refer to internet and text books for understanding it more precisely. Read more maths topics of different grades such as Steps in problem solving in the next session here.