On a map with a scale of 1:5000000, the distance between City A and City B is measured to be 9 cm. A car drives from city A to city B, traveling 90 kilometers per hour, how many hours can it reach city B?
在一幅比例尺是1：5000000的图上，量得甲城到乙城的距离是9厘米．一辆汽车从甲城开往乙城，每时行驶90千米，几小时能到达乙城？
<gadget id="calculator">1 / 5_000_000</gadget>
<output>1/5_000_000 = around 0</output>

<gadget id="calculator">9 / (1/5_000_000) / 100_000 / 90</gadget>
<output>5</output>

<result>5</result>