The new price was reduced by 40% after a 25% discount on a book during the sale. Then the actual selling price of this book is the original price. (answer written as a percentage)
展销时一本书减价25%，这一新的价格又被减少了40%．则这一本书的实际售价是原价的多少．(答案写成百分数)
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

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

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/4) * (3/5)</gadget>
<output>9/20 = around 0.45</output>

<result>9/20 = around 0.45</result>