A book has 200 pages. If you read (2/5) of the whole book on the first day, how many pages should you start reading on the second day?
一本书有200页，第一天读了全书的(2/5)，第二天应从多少页开始读起．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">200 * (2/5)</gadget>
<output>80</output>

<gadget id="calculator">80 + 1</gadget>
<output>81</output>

<result>81</result>