Correct Answer - Option 1 : 333.625
Given:
Side of the square shaped grass field = 20.5 m
The length of the rope is 10.5 m
Concept Used:
Area of square = Side2
Area of sector = θ/360 × πr2
Calculation:
Area of square grass field = 20.52 = 420.25 m2
Area of sector in which cow can gaze = 90/360 × πr2 = 90/360 × 22/7 × 10.52 = 86.625
∴ Area in which cow can not gaze = 420.25 - 86.625 = 333.625 m2