Kobayashi reads an 80-page story book. He reads (1/4) of it on the first day, and how many pages should he start reading on the second day.
小林看一本80页的故事书，第一天看了它的(1/4)，第二天应从第多少页开始看．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">80 * (1/4)</gadget>
<output>20</output>

<gadget id="calculator">20 + 1</gadget>
<output>21</output>

<result>21</result>