A book has 200 pages. Xiao Ming reads the whole book (1/5) on the first day, reads all (1/4) on the second day, and which page does he start to read on the third day?
一本书200页，小明第一天看全书的(1/5)，第二天看全部(1/4)，第三天从第几页开始看？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/5) + (1/4)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">200 * (9/20)</gadget>
<output>90</output>

<gadget id="calculator">90 + 1</gadget>
<output>91</output>

<result>91</result>