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1970 AMC 12 Question 32

AMC12 · 1970 AMC 12

Question 32

$A$ and $B$ travel around a circular track at uniform speeds in opposite directions, starting from diametrically opposite points. If they start at the same time, meet first after $B$ has travelled $100$ yards, and meet a second time $60$ yards before $A$ completes one lap, then the circumference of the track in yards is:
  1. $400$
  2. $440$
  3. $480$
  4. $560$
  5. $880$