Obviously read a 190-page story book, read an average of 15 pages a day in the first 4 days, and finish reading in the remaining 10 days, how many pages a day on average?
明明看一本190页的故事书，前4天平均每天看15页，剩下的10天看完，平均每天看多少页？
<gadget id="calculator">15 * 4</gadget>
<output>60</output>

<gadget id="calculator">190 - 60</gadget>
<output>130</output>

<gadget id="calculator">130 / 10</gadget>
<output>13</output>

<result>13</result>