A ship travels 30 nautical miles per hour, departs from Port A at 7:30 am, rests for an hour at noon, and arrives at Port B at 3:30 pm. How many nautical miles is the waterway between the two ports?
一艘轮船每小时行30海里，上午7时30分从甲港出发，中午休息1小时，下午3时30分到达乙港，两个港口之间的水路长多少海里？
<gadget id="calculator">30 * 7</gadget>
<output>210</output>

<result>210</result>