9 students went to the park to row boats. They rented a boat that can only take 5 people, so they kept 5 of them rowing, and the rest played on the shore, and then took turns rowing. If the boat is rented for 3 hours (excluding the time of boarding and disembarking) , everyone spends the same amount of time rowing, so how many minutes did each person spend on the shore?
9位同学到公园划船，他们租用了一条只能乘坐5人的小船，于是保持其中5人划船，其余的人在岸上游玩，然后轮流划船，如果小船租用了3小时(不计上、下船时间)，每人划船的时间相同，那么，每人在岸上游玩了多少分钟．
<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">3 * (4/9) * 60</gadget>
<output>80</output>

<result>80</result>