Xiaoyu reads a science fiction novel, originally planned to finish it in 45 days, but actually reads 25 pages a day, which is 5 days less than the original plan. How many pages does this book have?
小玉看一本科幻小说，原计划45天看完，实际每天看25页，比原计划少用了5天．这本书有多少页？
<gadget id="calculator">45 - 5</gadget>
<output>40</output>

<gadget id="calculator">25 * 40</gadget>
<output>1_000</output>

<result>1_000</result>