Modes and Scales: Understanding the Interval of a 3rd

Which scale is the only one to use the interval of a 3rd?

A. mode

B. whole tone

C. pentatonic

D. chromatic

The answer is A (mode).

Mode is the scale that is the only one to use the interval of a 3rd. Octave-repeatable scale is the mode of permutation, which means the scale has a start and end point that are shifted. This distinguishes mode from other scales.

When it comes to how modes work with scales, excluding any upbeats or anacruses, you can find the mode by taking the lowest beginning note in the first downbeat in the left hand and making the same amount of steps along the sequence of modes. This process will help you identify the mode that fits the criteria.

For example, the leading scale is quotable at the octave. This means that the answer is option A, mode, as it is the only scale that uses the interval of a 3rd.