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In 2004 a city department bought 500 dozen pencils at 40 cents per dozen.
In 2007, only 75% as many pencils were bought in 2004,
but the price was 20% higher than the 2004 price.
The total cost of the pencils bought in 2007 was
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According to the problem, in 2007 0.75*500 dozens of pencils was bought, i.e. 375 dozen.
The price in 2007 was 1.2*40 cents per dozen, or 48 cents per dozen.
So, the answer to the problem's question is this product 48*375 = 18000 cents, or 180 dollars.
Solved.
This problem teaches us to very important skills, which is to multiply numbers correctly.