Book: RS Aggarwal - Mathematics
Chapter: 18. Area of Circle, Sector and Segment
Subject: Maths - Class 10th
Q. No. 3 of Multiple Choice Questions (MCQ)
Listen NCERT Audio Books to boost your productivity and retention power by 2X.
3
The difference between the circumference and radius of a circle is 37 cm. The area of the circle is
Let the radius if circle be r
Circumference of circle = 2πr
Difference between the circumference and radius of a circle = 37 cm
⇒ 2πr – r = 37 cm
⇒ 2 × 22/7 × r – r = 37 cm
⇒ 44/7 × r – r = 37 cm
⇒ (44/7 – 1) × r = 37 cm
⇒ 37/7 × r = 37 cm
⇒ r = 37 × 7/37
⇒ r = 7 cm
Area of circle = πr2
= 22/7 × 7 × 7 cm2
= 22/7 × 49 cm2 = 22 × 7 cm2 = 154 cm2
∴ Area of the circle is 154 cm2
