<PRE><B>Question 123792</B>
Call the area purchased at 20,000 per acre as X.  Then the portion purchased at 10,000 per acre is (70-X).

Since the total cost is 900,000 we have the following equation:

900,000 = 20,000*X + 10,000*(70-X)

or

900,000 = 20,000*X + 700,000 - 10,000*X

0r

200,000 = 10,000 * X

20 = X

So the developer purchased 20 acres at 20,000 and (70-20) or 50 acres at 10,000.

Check:

20*20,000 + 50*10,000 = 400,000 + 500,000 = 900,000

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