Xiaohong reads a 120-page comic book. On the first day, she reads 10 pages. On the second day, she reads twice as many pages as on the first day. How many pages should she read on the third day?
小红看一本120页的连环画，第一天看10页，第二天看的页数是第一天的2倍，第三天应从第多少页看起．
<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<gadget id="calculator">10 + 20 + 1</gadget>
<output>31</output>

<result>31</result>