It takes 18 hours for ship A to sail 360 kilometers against the current, and 10 hours to return to the original place; it takes 15 hours for ship B to sail the same distance against the current, how many hours does it take to return to the original place?
甲船逆水航行360千米需18小时，返回原地需要10小时；乙船逆水航行同样一段距离需要15小时，返回原地需要多少小时？
<gadget id="calculator">360 / 15</gadget>
<output>24</output>

<gadget id="calculator">360 / 10</gadget>
<output>36</output>

<gadget id="calculator">360 / 18</gadget>
<output>20</output>

<gadget id="calculator">36 - 20</gadget>
<output>16</output>

<gadget id="calculator">16 / 2</gadget>
<output>8</output>

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">24 + 16</gadget>
<output>40</output>

<gadget id="calculator">360 / 40</gadget>
<output>9</output>

<result>9</result>