The area of a circle is increased by 22 cm² when its

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The area of a circle is increased by 22 cm² when its radius is increased by 1 cm. The original radius of the circle is

1. 3 cm
2. 5 cm
3. 7 cm
4. 9 cm

Correct Option: A

Using Rule 14,
π(r + 1)² – πr² = 22
⇒ π(r² + 2r + l - r²) = 22
⇒ 2πr + π = 22

⇒	22	(2r + 1) = 22
	7

⇒ 2r + 1 = 7
⇒ 2r = 6
⇒ r = 3 cm.