Xinxin reads a 140-page story book, read the whole book (2/7) on the first day, read 30 pages on the second day, how many pages should be read from the third day.
欣欣读一本140页的故事书，第一天读了全书的(2/7)，第二天读了30页，第三天应从多少页读起．
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">140 * (2/7)</gadget>
<output>40</output>

<gadget id="calculator">40 + 30 + 1</gadget>
<output>71</output>

<result>71</result>