Xiaohua reads a 250-page story book, and reads 75 pages in the first 3 days. According to this calculation, how many days will it take him to finish reading the book? (answer with ratio)
小华看一本250页的故事书，前3天看了75页，照这样计算，他看完这本书共要几天？(用比例解答)
<gadget id="calculator">250 * 3</gadget>
<output>750</output>

<gadget id="calculator">750 / 75</gadget>
<output>10</output>

<result>10</result>