A ship sails from port A to port B at a speed of 45 km/h and arrives in 6 hours. The ship took 1 hour less to return from port B to port A. What was the speed when it returned?
一艘轮船以45千米/时的速度从甲港驶往乙港，6小时后到达．这艘轮船从乙港返回甲港时少用了1个小时，返回时的速度是多少？
<gadget id="calculator">45 * 6</gadget>
<output>270</output>

<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<gadget id="calculator">270 / 5</gadget>
<output>54</output>

<result>54</result>