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2013 AMC 8 Question 25

AMC8 · 2013 AMC 8

Question 25

A ball with diameter $4$ inches starts at point $A$ to roll along the track shown. The track is comprised of $3$ semicircular arcs whose radii are $R_1 = 100$ inches, $R_2 = 60$ inches, and $R_3 = 80$ inches, respectively. The ball always remains in contact with the track and does not slip. What is the distance in inches the center of the ball travels over the course from $A$ to $B$?

Question illustration
  1. $238 \pi$
  2. $240 \pi$
  3. $260 \pi$
  4. $280 \pi$
  5. $500 \pi$