Yang Yang is reading a popular science book and has read 60 pages, leaving (1/3) of the book unread. How many pages are there in this textbook? (solution by equation)
阳阳正在读一本科普读物，已经读了60页，还剩下这本书的(1/3)没有读．这本科普书一共多少页？(用方程解)
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">60 / (2/3)</gadget>
<output>90</output>

<result>90</result>