The distance between A and B is 420 kilometers, and a car has traveled the whole distance (4/7). How many kilometers has this car traveled?
甲乙两地相距420千米，一辆汽车行驶了全程的(4/7)，这辆汽车行驶了多少千米？
<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">420 * (4/7)</gadget>
<output>240</output>

<result>240</result>