A story book, after Xiaodong read 60 pages, there are still (2/3) of this book left unread, how many pages does this book have? (solution by equation)
一本故事书，小东看了60页后，还剩下这本书的(2/3)没有看，这本书一共有多少页？(用方程解)
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">60 / (1/3)</gadget>
<output>180</output>

<result>180</result>