Xiaoying borrowed a novel from the library, read 8 pages a day, read half of the book in 15 days, and then read 10 pages a day, and finished it within the borrowing period. How many days is the borrowing period for this book?
小英从图书馆借来一本小说，每天看8页，15天看了这本书的一半，以后每天看10页，正好在借期内看完，这本书的借期是多少天？
<gadget id="calculator">15 / 10</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">8 * (3/2)</gadget>
<output>12</output>

<gadget id="calculator">12 + 15</gadget>
<output>27</output>

<result>27</result>