how to recognize numbers in piano?? Any advice?

[Dennis1990]

Im trying to learn how to modulate from one key to another.

And in a tutorial it said to just find the 5 7 chord on the key you want to modulate to.

Im trying to wrap my head around this number concept in piano but get confused not knowing if they mean chords or notes.

Example:
Playing a 3 4 5 chord?

Any advice?

 

[scrapheaper]

In the 5 7 chord:
5 refers to the degree of the scale the chord is based on, more usually written V in roman numerals to prevent this kind of confusion.
e.g the 5 chord of F major is C major.

7 refers to the added notes to this chord beyond the usual triad- in this case added flat 7.
e.g. a C7 chord is C (1) E (3) G (5) and Bb (7)

Overall: if the key you want to modulate to is say, G minor, then the 5 7 chord or V7 chord you should use to modulate to is D7, (because D is the fifth degree of the D minor scale)