A car drives from A to B. If it travels 84 kilometers per hour, it takes 6 hours to reach it. If it travels 90 kilometers per hour, how many hours does it take? (Answer with the knowledge of proportion)
一辆汽车从甲地开往乙地，如果每小时行84千米，则6小时可以到达，如果每小时行90千米，几小时可以到达？(用比例的知识解答)
<gadget id="calculator">84 * 6</gadget>
<output>504</output>

<gadget id="calculator">504 / 90</gadget>
<output>28/5 = around 5.6</output>

<result>28/5 = around 5.6</result>