The speeds of the two ships A and B in still water are 22 km and 18 km respectively. The two ships set out from the port successively along the water, and B set off 2 hours earlier than A. Can you catch up with B in an hour?
静水中甲、乙两船的速度为22千米、18千米，两船先后自港口顺水开出，乙比甲早出发2小时，若水速是每小时4千米，问甲开出后几小时可追上乙？
<gadget id="calculator">18 + 4</gadget>
<output>22</output>

<gadget id="calculator">22 * 2</gadget>
<output>44</output>

<gadget id="calculator">22 + 4</gadget>
<output>26</output>

<gadget id="calculator">26 - 22</gadget>
<output>4</output>

<gadget id="calculator">44 / 4</gadget>
<output>11</output>

<result>11</result>