Monopolist maximize profit by producing where marginal revenue is equal to marginal cost. The old and young clients will be charged $55 and $45 respectively.
Define marginal revenue?
- The cash an organization receives for each extra sale is known as marginal revenue.
- In other words, it calculates how much money a company would make from selling one more good. 
- For instance, a baker's marginal revenue is $2 if they sell an additional loaf of bread for $2.
- Change in Revenue / Change in Quantity equals Marginal Revenue.
- The profit made by a company or individual when one more unit is produced and sold is known as a marginal profit. 
- Marginal refers to the additional expense or profit made when producing the following unit. 
- In terms of economics, marginal refers to having slightly more or slightly less of something. 
- It speaks of the results of using or providing one more unit of a good or service.
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