Liu Ling reads 2,000 pages of a book, an average of 103 pages per day. After 15 days of reading, how many pages are left?
刘玲读一本书2000页，平均每天读103页，读了15天，还剩多少页没读？
<gadget id="calculator">103 * 15</gadget>
<output>1_545</output>

<gadget id="calculator">2_000 - 1_545</gadget>
<output>455</output>

<result>455</result>