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cssears
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Compnay Z only sells chairs and tables

by cssears Wed Feb 17, 2010 8:46 pm

4th edition > Guide 2 > Chapter 3 > In action Problem #15 > pg56

In the answer explanation it instructs the student to pick smart numbers for the one of the items and its quantity. How do you derive from the question stem that you can pick number for both the price and the quanity of one of the items?
Ben Ku
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Re: Compnay Z only sells chairs and tables

by Ben Ku Thu Feb 25, 2010 12:49 am

First of all, I think it seems fairly obvious that neither (1) nor (2) are sufficient on their own. The question is asking for revenue, which is price * quantity. Statement (1) gives price, but not quantity. Statement (2) gives quantity, but not price.

Both of the statements provide information about how the table is related to the chair. Because of that constraint (meaning, because we want to preserve that relationship), we pick smart numbers for one of the items, and then use the information in the statements to obtain the information for the other item.

For example, in statement (2), it says, Company Z sold 20% fewer tables than chairs. You don't want to pick smart numbers for both tables and chairs. Instead, you want to assign a smart number for the number of chairs sold, and relate tables to the "20% fewer" piece of information.

Hope that makes sense.
Ben Ku
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ManhattanGMAT