# Guitar Pickin'

Pro Problems > Math > Statisics and Probabilities > Counting Principles## Guitar Pickin'

Owen is picking out random tunes on his guitar. He can play either half notes, quarter notes, or eighth notes. Each pluck can be one of the tones of the scale (C, C#, D, D#, E, F, F#, G, G#, A, A#, B). If he wanted to play every possible three-note tune, and he could do one tune every 20 seconds, how many days would it take him to play all of them?

[No calculators, please]

## Solution

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