The speeds of A and B in still water are 24 and 32 km/h respectively. Two ships set off in the same direction at the same time from two ports 336 kilometers apart. Ship A is in front and ship B is behind. How many hours will it take for ship B to catch up with ship A?
甲、乙两船在静水中的时速分别为24和32公里．两船在相距336公里的两港同时同向出发，甲船在前，乙船在后，问几小时后乙船追及甲船？
<gadget id="calculator">32 - 24</gadget>
<output>8</output>

<gadget id="calculator">336 / 8</gadget>
<output>42</output>

<result>42</result>