First of all, suppose that the original unit price of the bookcase is X yuan, then the unit price after each unit price rises by 20 yuan is (x+20) yuan due to market price changes. According to the equivalence relation: the number of bookcases originally planned for 4000 yuan = the number of bookcases actually planned for 4400 yuan, the equation can be obtained, and the answer can be obtained by solving the equation.

Answer process:

The original unit price of a bookcase is X yuan, which is deduced from the meaning of the question:

4000/x =4400/(x+20)

Solution: x=200,

It is verified that x=200 is the solution of the original fractional equation.

Answer: The original unit price of bookcase is 200 yuan.

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