Page 195 - Math Genius C4

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\\September 30, 2025 9:51 AM Bharat Arora P-9 Reader _________________________ Date: ___________________74

Now, let us find the area of the figure given activity
Think Tank Logical Thinking Logical Thinking
below. Use the square grid to draw two plane figures with a perimeter of 12 cm
1. How many rectangles can
you draw with 15 unit squares? but with different areas.
2. State whether the following
statements are true or false. finding area using geo Dotted Paper
(a) Two same shapes always have the
same area. We can also find the area of a plane figure using geo dotted paper.
(b) Doubling both the length and the
width of a rectangle doubles its Each unit on the geo dotted paper measures 1 cm.
area.
(c) If two rectangles have equal areas, So, each square on it has sides of 1 cm and an area of 1 sq. cm.
Here, the triangle does not contain only they must have equal perimeters. example: Find the area of the following plane figures drawn on a dot grid in sq. cm

complete squares. It has 6 complete squares by counting the number of squares in the interior of each.
and 4 half squares.
(a) (b) (c)

1
2
1 1
2 1
2 3 1 1 1
2 2 3 2 2
4 5 6 1 1 1 Solution: (a) Area = 9 sq. cm (b) Area = 7 sq. cm (c) Area = 11 sq. cm
2 4 5 6 2 2

6 + 1 + 1
Number of complete squares = 6 + 2 Practice time 10B

So, the area of the triangle is 8 square units. 1. Find the area of each figure drawn on a square grid by counting the number

example 2: Find the area of the following figure drawn on a square grid. Take the of squares covered by the shape (each square = 1 sq. cm).
side of a unit square as 1 unit.
1 cm
1 cm

d
F

A C
1 1
2 2
Solution: Here, number of complete squares = 10 1 1
2 2
Number of half squares = 4 B E G

2 half squares make a complete square. 4 half squares = 2 squares

Thus, the area of the figure = 10 + 2 = 12 square units (sq. units)

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