Ruoting is visiting the Lijiang River Scenic Area in Guilin. She takes a motorboat down the water and returns to the boarding place. The current speed is 2 kilometers per hour, and the speed of the motorboat in still water is 18 kilometers per hour. Over 3 hours, how many kilometers can Ruoting visit at most?
若婷在桂林漓江风景区游览，乘坐摩托艇顺水而下，然后返回登艇处，水流速度是2千米/时，摩托艇在静水中的速度是18千米/时，为了使游览时间不超过3小时，若婷最多可以游览多少千米？
<gadget id="calculator">80 / 3</gadget>
<output>80/3 = around 26.666667</output>

<result>80/3 = around 26.666667</result>