Example 4: Two people, A and B, travel eastward at the same time from two places 24 kilometers apart. A rides a bicycle and travels 13 kilometers per hour, and B walks 5 kilometers per hour. How many hours can A catch up with B?
例4：甲乙两人分别从相距24千米的两地同时向东而行，甲骑自行车每小时行13千米，乙步行每小时走5千米．几小时后甲可以追上乙？
<gadget id="calculator">13 - 5</gadget>
<output>8</output>

<gadget id="calculator">24 / 8</gadget>
<output>3</output>

<result>3</result>