The amount of peppers that one pepper plant will produce depends on the variety of the peppers on the plant.
Some pepper plants will produce up to 70 peppers per plant while some other types of pepper plants will only produce around 6 peppers per pepper plant.
Pepper plants that bear the thicker walled peppers will grow around 5 or 6 peppers per plant while the smaller walled peppers will grow around 30 to 70 peppers per pepper plant.