Xiao Ming reads a book. He reads (1/5) of the whole book on the first day, and reads 18 pages on the second day. The ratio of those who have read to those who have not read is 11:19. How many pages are there in the book?
小明看一本书，第一天看了全书的(1/5)，第二天看了18页，已看与未看的比是11：19，全书有多少页？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">11 + 19</gadget>
<output>30</output>

<gadget id="calculator">19 / 30</gadget>
<output>19/30 = around 0.633333</output>

<gadget id="calculator">(1/5) + (19/30)</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 - (5/6)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">18 / (1/6)</gadget>
<output>108</output>

<result>108</result>