A book, I read it (5/9) on the first day, the rest (1/5) on the second day, and the rest (1/4) on the third day, and there are 160 pages left , how many pages is this book?
一本书，第一天看了它的(5/9)，第二天看了余下的(1/5)，第三天看了再余下的(1/4)，这时还剩160页，这本书多少页？
<gadget id="calculator">1 / 4</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">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">1 - (5/9)</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">160 / (3/4) / (4/5) / (4/9)</gadget>
<output>600</output>

<result>600</result>