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stickers. In other words, if area of 1 sticker is 1 sq. unit or 1 sq. cm, then the area of the rectangular
sheet of paper = 108 sq. cm.

So, we can say the region enclosed by a plane figure is called its area.
Think! What will happen when Seema tries to cover the sheet of paper with circular smileys of
diameter 1 cm?

As you can see, smileys (circles) cannot be activity
packed tightly without gaps in between. So, it Try using different shapes (triangle and
is difficult to get an accurate measurement of rectangle) to fill a certain space (without
the area using circles as units. Here, the same overlaps and gaps) and find out the merits associated
rectangle is packed in two different ways with with using a square shape to find the area rather than
circles—the first one has 108 circles, and the another shape. List out the points that make a square the
second one has 115 circles. best shape to use to measure area.

Area on Square Grid Paper

As we have discussed, the boundary of a plane figure is its perimeter
and the region enclosed by a closed figure is called its area. We can
find the area with the help of a squared grid paper.

Count the number of squares enclosed in the adjoining figure.
On counting, we find that there are 15 squares enclosed in the figure.
Number of squares enclosed = Area of the figure
Hence, the area of the figure is 15 sq. units.

Area of Irregular Figures

Can you find out the area of the given figure?
It is difficult to find the area of the given figure by only observation.
In such situations, the following convention is adopted:
1. The complete squares in the enclosed region are counted and the
area of 1 complete square is counted as 1 sq. unit.
2. The portions of the area, which are less than half a square are
considered as 0 sq. unit.
3. The squares that are more than half-filled squares in the enclosed
region are taken as 1 sq. unit each.
4. Exactly half-filled squares are counted as each having an area of
1

2 sq. unit.

183
183 Perimeter and Area
and Ar
ea
P
erimeter