Two motorboats sail from East Harbor to West Harbor, which is 324 kilometers apart at the same time. When Boat B arrives at West Harbor, Boat A is still 52.8 kilometers away from West Harbor. It is known that Boat A travels 45.2 kilometers per hour. How much does Boat B travel per hour? km?
两艘汽艇同时从东港开往相距324千米的西港，当乙艇到达西港时，甲艇离西港还有52.8千米，已知甲艇每小时行45.2千米，求乙艇每小时行多少千米？
<gadget id="calculator">324 - 52.8</gadget>
<output>271.2</output>

<gadget id="calculator">271.2 / 45.2</gadget>
<output>6</output>

<gadget id="calculator">324 / 6</gadget>
<output>54</output>

<result>54</result>