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1953 AMC 12 Question 27

AMC12 · 1953 AMC 12

Question 27

The radius of the first circle is $1$ inch, that of the second $\dfrac12$ inch, that of the third $\dfrac14$ inch and so on indefinitely. The sum of the areas of the circles is:
  1. $\dfrac{3\pi}{4}$
  2. $1.3\pi$
  3. $2\pi$
  4. $\dfrac{4\pi}{3}$
  5. none of these