Two cars, A and B, drive from cities A and B, which are 504 km apart, at the same time. Car A travels 45 km per hour, which is slower (1/4) than car B per hour. How long does it take for the two cars to meet?
甲乙两辆汽车同时从相距504km的A，B两城相对开出，甲车每小时行45km，比乙车每h的速度慢(1/4)，几小时两车相遇？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">45 / (3/4)</gadget>
<output>60</output>

<gadget id="calculator">45 + 60</gadget>
<output>105</output>

<gadget id="calculator">504 / 105</gadget>
<output>24/5 = around 4.8</output>

<result>24/5 = around 4.8</result>