The distance between places A and B is 420 kilometers. Cars A and B drive toward each other from places A and B at the same time, and meet each other in 3 hours. It is known that the speed of car B is (3/4) the speed of car A, how many kilometers does car A travel per hour?
A、B两地相距420千米，甲、乙两车分别从A、B两地同时相向而行，3小时相遇．已知乙车速度是甲车速度的(3/4)，甲车每小时行多少千米？
<gadget id="calculator">420 / 3</gadget>
<output>140</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 + (3/4)</gadget>
<output>7/4 = around 1.75</output>

<gadget id="calculator">140 / (7/4)</gadget>
<output>80</output>

<result>80</result>