Minor Pentatonics
The Minor Pentatonic Scale is a scale which retains a Minor sound but only uses 5 notes.
The black keys on a keyboard represent a Pentatonic Scale.

The Minor Pentatonic formed by the black keys starts on Eb: Eb, Gb, Ab, Bb, Db This gives us the Interval pattern: Root, Min 3rd, Per 4th, Per 5th, Min 7th.
A Minor Pentatonic
A Minor is made up from: A, B, C, D, E, F and G. In Degrees: A(I), B(II), C(III), D(IV), E(V), F(VI), G(VII).
We construct all Minor Pentatonics by using the I, III, IV, V and VII Degrees of the Major Scale giving us: A(I), C(III), D(IV), E(V), G(VII).
A Minor Pentatonic: A, C, D, E, G (Root, Min 3rd, Per 4th, Per 5th, Min 7th)

Other Minor Pentatonics
Here's a table of all the other Minor Pentatonics in each key...
| KEY / INTERVAL | I | III | IV | V | VII |
| A# | A# | C# | D# | E# | G# |
| D# | D# | F# | G# | A# | C# |
| G# | G# | B | C# | D# | F# |
| C# | C# | E | F# | G# | B |
| F# | F# | A | B | C# | E |
| B | B | D | E | F# | A |
| E | E | G | A | B | D |
| A | A | C | D | E | G |
| D | D | F | G | A | C |
| G | G | Bb | C | D | F |
| C | C | Eb | F | G | Bb |
| F | F | Ab | Bb | C | Eb |
| Bb | Bb | Db | Eb | F | Ab |
| Eb | Eb | Gb | Ab | Bb | Db |
| Ab | Ab | Cb | Db | Eb | Gb |
3 Minor Pentatonic Scales per Key (again)!
You might notice that the A Minor Pentatonic, D Minor Pentatonic and E Minor Pentatonic all contain no sharps or flats. What this means is that they will all fit into the key of C and it's realtive Natural Minor of A. Giving you three options to choose from. I suggest experimenting by playing each one over a A Minor chord progression (e.g. Am, Em, Dm, Em) to hear how they sound.