F major/B
The F major chord consists of the F (Perfect unison), A (Major third) and C (Perfect fifth) notes, with B as the bass note.

How to play the F major/B chord
- Play B as the lowest bass note in the left hand
- Find F (Root) on the piano keyboard
- Add A (Major third) — 4 semitones above F
- Add C (Perfect fifth) — 7 semitones above F
- Press all 4 notes simultaneously to sound the F major/B chord