Wang Ling reads a 240-page storybook, 30 pages a day, and after 3 days, she has to finish the rest within 6 days. How many pages do she read on average every day?
汪玲看一本240页的故事书，每天看30页，看了3天后，剩下的要在6天内看完，平均每天看多少页？
<gadget id="calculator">30 * 3</gadget>
<output>90</output>

<gadget id="calculator">240 - 90</gadget>
<output>150</output>

<gadget id="calculator">150 / 6</gadget>
<output>25</output>

<result>25</result>