If the radius of a sphere is increased by 2 cm, its surface area is increased by 464π cm². What is the radius of the original sphere? -
Answer & explanation
Correct answer: option 3
Increase in surface area = 4 \(\pi \) (r + 2)² - 4\(\pi \) r²
464 \(\pi \) = 4 \(\pi \) ( 4r + 4) 448 \(\pi \) = 16 \(\pi \) r r = 28 cm