A two dimensional picture of a circular onion ring is shown at the right. The inner radius of the onion ring is x cm. and the thickness of the ring is 1 cm. Which of the numbered choices represents the area, in square centimeters, of the onion ring (the shaded region)?

Question

1) (2x+1)*pi
2) 2*pi
3) 2x*pi
4) pi

Answer 1

Since you can't show the diagram, I will surmise the following

inner radius --- x
outer radius --- x+1

area of onion ring
= π(x+1)^2 - x^2)
= π(x^2 + 2x + 1 - x^2)
= π(2x+1) , looks like the first choice