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1975 AMC 12 Question 11

AMC12 · 1975 AMC 12

Question 11

Let $P$ be an interior point of circle $K$ other than the center of $K.$ Form all chords of $K$ which pass through $P,$ and determine their midpoints. The locus of these midpoints is
  1. a circle with one point deleted
  2. a circle if the distance from $P$ to the center of $K$ is
    less than one half the radius of $K;$ otherwise a circular arc of
    less than $360^\circ$
  3. a semicircle with one point deleted
  4. a semicircle
  5. a circle