Tick the correct answer in the following and justify your choice : If the perimeter and the area of a circle are numerically equal, then the radius of the circle is
(A) 2 units (B) π units (C) 4 units (D) 7 units

Solution:

Given that the perimeter and area of the circle are numerically equal.

Let's assume a circle of radius 'r'.

Circumference of the circle = 2πr

Area of circle = πr²

The circumference of the circle and the area of the circle are equal.

Thus, we have 2πr = πr²

2 = r

Therefore, the radius of the circle is 2 units. Hence, the correct answer is A.

☛ Check: NCERT Solutions for Class 10 Maths Chapter 12

Video Solution:

Tick the correct answer in the following and justify your choice : If the perimeter and the area of a circle are numerically equal, then the radius of the circle is (A) 2 units (B) π units (C) 4 units (D) 7 units

NCERT Solutions Class 10 Maths Chapter 12 Exercise 12.1 Question 5

Summary:

The radius of the circle is 2 units if the perimeter and the area of a circle are numerically equal.

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