An Ad Agency Is Developing a Campaign to Promote a Business

question 40

Multiple Choice

An ad agency is developing a campaign to promote a business opening in a new mall development. To develop an appropriate mailing list, they decide to purchase lists of credit card holders from MasterCard and American Express. Combining the lists, they find the following: 40 percent of the people on the list have only a MasterCard and 10 percent have only an American Express card. Another 20 percent hold both MasterCard and American Express. Finally, 30 percent of those on the list have neither card. Suppose a person on the list is known to have a MasterCard. What is the probability that person also has an American Express card?

• A) .20
• B) .33
• C) .18
• D) .70
• E) .90

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Definitions:

Equilibrium Price (P)

The price at which the quantity of a product demanded by consumers equals the quantity supplied by producers, leading to market balance.

Equilibrium Price

Equilibrium price is the price at which the quantity of a good or service demanded by consumers equals the quantity supplied by producers, resulting in a stable market condition.

Demand Increases

A situation where consumers are willing and able to purchase more of a product or service at the same price, shifting the demand curve to the right.

Supply Decreases

This term describes a situation in which the quantity of a good or service that producers are willing and able to offer for sale at various prices diminishes.