Do I need multiple Classes?

I have a question about a project I'm working on. The direction's are:
//Start
Design a class named Person with fields for holding a person's name, address, and telephone number. Write one or more constructors and the appropriate mutator and accessor methods for the class's fields.
Next, design a class named Customer, which is derived from the Person class. The Customer class should have a field for a customer number and a boolean field indication whether the customer wishes to be on a mailing list. Write one or more constructors and the appropriate mutator and accessor methods for the class's fields. Demostrate an object of the customer class in a simple program (CustomerDemo).
//End
My question is this, do I need to make 3 different classes? Why does the project require me to make a Person class, and a Customer class? Why not just combine the Person class and Customer class, then make the driver?

CS_Student001 wrote:
Why not just combine the Person class and Customer class, ...?Because not every Person is also a Customer of yours, with a customer number and a boolean that stores whether they want to be on a mailing list.
Imagine an Employee class. An Employee has a name, adress, and a phone number, but not a customer number. Instead, his pay could be stored in the Employee class. Had you combined Person and Customer, youd have to double the Name, adress, phone number parts. As cotton.m suggested, "inheritance" is the key google word here.

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Peetzore wrote:
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Edited by: mpjava on Jun 2, 2009 1:29 AM
Edited by: mpjava on Jun 2, 2009 1:30 AM

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