A storybook has 160 pages. After 8 days of reading, there are still 40 pages left to read. How many pages do you read on average every day?
一本故事书共160页，看了8天后，还剩下40页没有看完，平均每天看多少页？
<gadget id="calculator">160 - 40</gadget>
<output>120</output>

<gadget id="calculator">120 / 8</gadget>
<output>15</output>

<result>15</result>