What is the rule for finding the name of a sharp major key or scale?
There are different rules. For major keys, the rule is this (by
the way, # means sharp):
C major scale- 0 sharps or flats
G major scale- 1 sharp - F sharp
D major scale- 2 sharps - F and C sharp
A major scale- 3 sharps - F, C, G sharp
E major scale- 4 sharps - F, C, G, D sharp
B major scale- 5 sharps - F, C, G, D, A sharp
F# major scale- 6 sharps - F, C, G, D, A, E sharp
C# major scale - 7 sharps - F, C, G, D, A, E, B sharp.
For major keys with flats:
F major scale - 1 flat - B flat
B flat major scale - 2 flats - B, E flat
E flat major scale - 3 flats - B, E, A flat
A flat major scale - 4 flats - B, E, A, D flat
D flat major scale - 5 flats - B, E, A, D, G flat
G flat major scale - 6 flats - B, E, A, D, G, C flat
C flat major scale - 7 flats - B, E, A, D, G, C, F flat
So as you might have noticed, in increasing order of sharps it
is: F, C, G, D, A, E, B. And the increasing order of flats is B, E,
A, D, G, C, F. If you notice the order of sharps is the opposite of
the order of flats.