Jiang Tao has been reading a 200-page storybook for 4 days, 20 pages a day. The rest is going to be read in 6 days. How many pages do you read on average every day?
江涛看一本200页的故事书，已经看了4天，每天看20页．剩下的准备用6天的时间看完，平均每天要看多少页？
<gadget id="calculator">20 * 4</gadget>
<output>80</output>

<gadget id="calculator">200 - 80</gadget>
<output>120</output>

<gadget id="calculator">120 / 6</gadget>
<output>20</output>

<result>20</result>