Fangfang reads a storybook, 25 pages a day for the first 4 days, and 35 pages a day for the next 6 days. How many pages does she read on average every day?
芳芳看一本故事书，前4天每天看25页，后6天每天看35页，平均每天看多少页？
<gadget id="calculator">4 * 25</gadget>
<output>100</output>

<gadget id="calculator">6 * 35</gadget>
<output>210</output>

<gadget id="calculator">100 + 210</gadget>
<output>310</output>

<gadget id="calculator">4 + 6</gadget>
<output>10</output>

<gadget id="calculator">310 / 10</gadget>
<output>31</output>

<result>31</result>