Xiaohong has been reading a 140-page storybook for 5 days, with an average of 16 pages per day, and she needs to finish it in 3 days. How many pages per day should she read on average?
小红看一本140页的故事书，已经看了5天，平均每天看16页，剩下要在3天看完，平均每天应看多少页？
<gadget id="calculator">16 * 5</gadget>
<output>80</output>

<gadget id="calculator">140 - 80</gadget>
<output>60</output>

<gadget id="calculator">60 / 3</gadget>
<output>20</output>

<result>20</result>