If a book is priced at 10 yuan per book, it can make a profit of 25%. If it wants to make a profit of 40%, how much should it be priced at per book?
一种书若定价每本10元，可盈利25%，若想盈利40%，则应定价为每本多少元？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">10 / (5/4)</gadget>
<output>8</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 + (2/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">8 * (7/5)</gadget>
<output>56/5 = around 11.2</output>

<result>56/5 = around 11.2</result>