Updated Math Question

The radius of circle A is 9 times greater than the radius of circle B. Which of the following statements is true?
A.The area of circle B is 9 times greater than the area of circle A.
B.The area of circle A is 9 times greater than the area of circle B
C.The area of circle B is 81 times greater than the area of circle A.
D.The area of circle A is 81 times greater than the area of circle B.

  1. 0
  2. 7
asked by Kim
  1. no, the answer is d)

    let the radius of first circle be r
    area = πr62
    let the area of 2nd circle be 9r
    area =π(9x)^2 = 81πr^2, which is 81 times larger.

    posted by Reiny

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