Civil Service Exam Reviewer · Measurement and Geometry · hard

If the radius is multiplied by 4, by what factor does the area of a circle increase?

  1. 4 times
  2. 64 times
  3. 8 times
  4. 16 times

Answer

D. 16 times

Solution

Area of a circle depends on the square of the length: 42 = 16.

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