If the radius of a circle is increased to twice its original length, how much will the area of the circle increase?
(a) 1.4 times
(b) 2 times
(c) 3 times
(d) 4 times

Solution:

Given, the radius of a circle is increased to twice its original length

We have to find the increase in area of the circle

Area of circle = πr²

Where, r is the radius of the circle

Now, r = 2r

Area of circle = π(2r)²

= 4πr²

Therefore, the area of the circle will be increased by 4 times.

✦ Try This: If the radius of a circle is increased to thrice its original length, how much will the area of the circle increase?

Given, the radius of a circle is increased to thrice its original length

We have to find the increase in area of the circle

Area of circle = πr²

Where, r is the radius of the circle

Now, r = 3r

Area of circle = π(3r)²

= 9πr²

Therefore, the area of the circle will be increased by 9 times.

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 11

NCERT Exemplar Class 7 Maths Chapter 9 Problem 30

If the radius of a circle is increased to twice its original length, how much will the area of the circle increase? (a) 1.4 times, (b) 2 times, (c) 3 times, (d) 4 times

Summary:

If the radius of a circle is increased to twice its original length, the area of the circle will increase by 4 times

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