If you open math book you will find a lot of mathematical
questions but you should have solve this question.
It is from class 10 rd sharma chapter 15.4 mensuration .
In this question we have to find the area of the shaded
region given that OE = 20 cm. In sector OSFT, square OEFG is inscribed.
It’s seen that, OEFG is a square of side 20 cm.
So its diagonal = √2 side = 20√2 cm
And, the radius of the quadrant = diagonal of the square
Radius of the quadrant = 20√2 cm
So,
Area of the shaded portion = Area of quadrant – Area of square
= ¼ πr2 – side2
= ¼ (22/7)(20√2)2 – (20)2
= ¼ (22/7)(800) – 400
= 400 x 4/7 = 1600/7 = 228.5 cm2