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# 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 = πr^{2}

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

Thus, we have 2πr = πr^{2}

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.

**☛ Related Questions:**

- The radii of two circles are 19 cm and 9 cm respectively. Find the radius of the circle which has circumference equal to the sum of the circumferences of the two circles.
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- The wheels of a car are of diameter 80 cm each. How many complete revolutions does each wheel make in 10 minutes when the car is travelling at a speed of 66 km per hour?

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