A story book has 216 pages in total, and it is read in three days. The number of pages read on the first day is the number of pages read on the second day (5/12), and the number of pages read on the second day is the total number of pages read in the other two days. (1/4), how many pages were read on the first day.
一本故事书共216页，分三天读完，第一天读的页数是第二天读的(5/12)，第二天读的页数是其它两天读的总页数的(1/4)，第一天读了多少页．
<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">43.2 * (5/12)</gadget>
<output>18</output>

<result>18</result>