How does a dot affect a note?
A dot affects a note by making it longer. The note becomes "longer by
half." To figure out the length or value of a dotted
note, use this formula: add the original value of the note to half of the
value of the note for the new value. So, a half note, for example, would
receive two counts (beats) in 4/4 time. With a dot added, it now would
receive three counts.
Using the formula, add the original value of the note (two counts) to half
of the value of the note (one count) for the new value (two plus one =
three) which is three counts.