The three chord, like the two chord is a minor chord, and again, let us use the more ambiguous minor 7th chord. This is played using the same shape, 2 frets up from the two chord.
Notice again that this time the notes on strings 3,4 & 5 are common with our previous five chord. Again, this means you can substitute one for the other, either sounding better depending on the song you have chosed.
Again, alternatively, the normal minor chord can be played by adding your little finger (4) like this: