A book has 240 pages. I read (1/3) of the book in the first week and 90 pages in the second week. How many pages are left?
一本书240页，第一周读了这本书的(1/3)，第二周读了90页，还剩下多少页？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">240 * (1/3)</gadget>
<output>80</output>

<gadget id="calculator">240 - 80 - 90</gadget>
<output>70</output>

<result>70</result>