Chapter 10.2

Question 1.

Find the areas of the following figures by counting square:

Solution:

(a) Number of full squares = 9

Area of 1 square = 1 sq unit

∴ Area of 9 squares = 9 x 1 sq unit

= 9 sq units.

So, the area of the portion covered by 9 squares = 9 sq units

(b) Number of full squares = 5

∴ Area of the figure = 5 x 1 sq unit = 5 sq units

(c) Number of full squares = 2

Number of half squares = 4

∴ Area of the covered figure = 2 x 1 + 4 x 12 = 2 + 2

= 4 sq units

(d) Number of full squares = 8

∴ Area of the covered portion of the figure = 8 x 1 sq unit

= 8 sq units.

(e) Number of full squares = 10

Area covered by the figure = 10 x 1 sq unit = 10 sq units.

(f) Number of full squares = 2

Number of half squares = 4

∴ Area of the covered figure = (2 x 1 + 4 x 12)

= (2 + 2) sq units = 4 sq units.

(g) Number of full squares = 4

Number of half squares = 4

∴ Area of the covered figure = (4 x 1 + 4 x 12)

= (4 + 2) sq units = 6 sq units.

(h) Number of full squares = 5

∴ Area of the covered figure = 5 x 1 sq unit = 5 sq units.

(i) Number of full squares = 9

∴ Area of the covered figure = 9 x 1 sq units

= 9 sq units.

(j) Number of full squares = 2

Number of half squares = 4

∴ Area of the covered figure =(2 x 1 + 4 x 12) sq units

= (2 + 2) sq units = 4 sq units.

(k) Number of full squares = 4

Number of half squares = 2

∴ Area of the covered figure = (4 x 1 + 2 x 12)sq units

= (4 + 4)sq units

= 5sq units

(l) Number of full squares = 4

Number of squares more than half = 3

Number of half squares = 2

∴ Area of the covered figure = (4 x 1 + 3 x 1 + 2 x 12 sq units

= (4 + 3 + 1) sq units = 8 sq units.

(m) Number of full squares = 6

Number of more than half squares = 8

Area of the covered figure = (6 x 1 + 8 x 1) sq units

= (6 + 8) sq units

= 14 sq units.

(n) Number of full squares = 9

Number of more than half squares = 9

∴ Area of the covered figure

= (9 x 1 + 9 x 1) sq units

= (9 + 9) sq units = 18 sq units.