Xiaojun reads a story book and reads 25 pages a day. After reading it for 6 days, he reads 5 pages and reads exactly half of the book. How many pages does this book have? (column comprehensive formula calculation)
小军看一本故事书，每天看25页，看了6天后，再看5页就正好看了这本书的一半．这本书有多少页？(列综合算式计算)
<gadget id="calculator">25 * 6</gadget>
<output>150</output>

<gadget id="calculator">150 + 5</gadget>
<output>155</output>

<gadget id="calculator">155 * 2</gadget>
<output>310</output>

<result>310</result>