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1987 AMC 12 Question 13

AMC12 · 1987 AMC 12

Question 13

A long piece of paper $5$ cm wide is made into a roll for cash registers by wrapping it $600$ times around a cardboard tube of diameter $2$ cm, forming a roll $10$ cm in diameter. Approximate the length of the paper in meters. (Pretend the paper forms $600$ concentric circles with diameters evenly spaced from $2$ cm to $10$ cm.)
  1. $36\pi$
  2. $45\pi$
  3. $60\pi$
  4. $72\pi$
  5. $90\pi$