" is the difference between the average cost and price of all merchandise in stock as used by the middlemen."

Markup

Explanation:

Markup is defined as the difference that exists between the selling price of a product and the average cost that was used in its production

This information is used by middle men to estimate the amount of profit they can make on sale of a product.

Usually the markup cost is incorporated into the cost incurred by the producer as a percentage of a product's cost.

This ensures middle men make some profit

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