If a publishing house issues a book at a price of 2.50 yuan each, it can issue 80,000 copies. If the price of a book increases by 0. 1 yuan, the circulation will be reduced by 2000 copies. If the income is not less than 200 thousand, ask for the highest price of this book.

If you add a 0.65438+ 0 yuan, you will lose 2000 copies.

Suppose the income is y yuan.

y =(2.5+0. 1a)×(80000-2000 a)

=200(25+a)×(40-a)

=-200(a？ - 15a- 1000)

=-200(a- 15/2)？ +2 1 1250

Y is a quadratic function.

When a= 15/2=7.5, the maximum value of y is 2 1 1250.

So the pricing at this time is 2.5+0. 1×7.5=3.25 yuan.

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