In the given figure, three sectors of a circle of radius 7 cm, making angles of 60°, 80° and 40° at the centre are shaded. Find the area of the shaded region.

Given:

Radius of circle = 7 cm

Let the sectors with central angles 80°, 60° and 40° be S_{1}, S_{2}, and S_{3} respectively.

Then, the area of shaded region = Area of S_{1} + Area of S_{2} + Area of S_{3} …………………….. (i)

∵ Area of sector = × πr^{2}

∴ Area of S_{1} = × × 7 × 7

= cm^{2}

Similarly, Area of S_{2} = × × 7 × 7

= cm^{2}

and Area of S_{3} = × × 7 × 7

= cm^{2}

Thus, using (i), we have

Area of shaded region = + +

=

= = 77 cm^{2}

__Hence, the area of shaded region is 77 cm ^{2}.__

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