Area
Area of a region is literally shows the number of square which can be fitted in the given region.
Here the above rectangle has length of 7 unit and breadth of 3 unit. When we find out the area of the above rectangle we get the number of square of same unit fitted in the given region.
To fill this region, we required 21 number of squares. So, a number which shows square required by a region to fill it, is known as area of that region.
Volume
Volume of a 3D shape is the number of cube required to fill the given 3D shape.
In the above figure here we can see that a cuboid is made up of different number of cube. This number represent the volume of given cuboid.
Perimeter
Perimeter of a 2D shape is the length of the outer boundary of that particular shape.
From our earth we can see total 42 nakcharta in which our earth move only in 36 nakchtra. It is related to the angle.
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