Person A and Person B travel towards each other from places A and B which are 300 kilometers apart at the same time, and meet each other after 6 hours. It takes 10 hours for A to travel from point A to point B, and how many hours does it take for B to travel from point B to point A?
甲乙两人同时分别从相距300千米的A，B两地相向而行，6小时后相遇，甲从A地到B地需10小时，乙从B地到A地需行几小时？
<gadget id="calculator">300 / 6</gadget>
<output>50</output>

<gadget id="calculator">300 / 10</gadget>
<output>30</output>

<gadget id="calculator">50 - 30</gadget>
<output>20</output>

<gadget id="calculator">300 / 20</gadget>
<output>15</output>

<result>15</result>