Huahua reads a book and has already read 72 pages, which happens to be the remaining (8/9). How many pages does this book have?
华华看一本书，已经看了72页，正好是剩下的(8/9)，这本书共有多少页？
<gadget id="calculator">8 / 9</gadget>
<output>8/9 = around 0.888889</output>

<gadget id="calculator">72 / (8/9)</gadget>
<output>81</output>

<gadget id="calculator">81 + 72</gadget>
<output>153</output>

<result>153</result>