A book with 200 pages, if you read 20% on the first day, what page should you start reading on the second day?
一本书200页，第一天读了20%，第二天应从第多少页开始读．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">200 * (1/5)</gadget>
<output>40</output>

<gadget id="calculator">40 + 1</gadget>
<output>41</output>

<result>41</result>