Complementary intervals

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What is the complementary interval of a major 3rd?

  • The second inteval that is needed to form a major triad, which is a minor 3rd.
  • The other intervals that are named as a 3rd: minor 3rd, diminished 3rd, augmented 3rd.
  • The interval that adds up to an octave with the major 3rd: a minor 6th.