How to get a single profit maximizing price when we cannot figure out how much customers willing to pay. For example, Group A wants to pay $20 and…

How to get a single profit maximizing price when we cannot figure out how much customers willing to pay.

For example, Group A wants to pay $20 and Group B wants to pay $10 for a product. Total potential customers is 40.

How do I figure a single profit maximizing price in this case?

Thank you