Li Nan reads a book, read the whole book (5/12) on the first day, read 30 pages on the second day, and left the whole book (1/6) unread. How many pages does this book have?
李楠看一本书，第一天看了全书的(5/12)，第二天看了30页，还剩下全书的(1/6)未看．这本书共有多少页？
<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(5/12) + (1/6)</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">1 - (7/12)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">30 / (5/12)</gadget>
<output>72</output>

<result>72</result>