When Xiao Ming reads a book, he has already read 72 pages, and he has not read the whole book (5/9). How many pages does this book have?
小明看一本书，已经看了72页，还剩全书的(5/9)没有看．这本书有多少页？
<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">72 / (4/9)</gadget>
<output>162</output>

<result>162</result>