From A to B, Xiao Ming takes 4 hours by car, traveling 30 kilometers per hour. It takes 6 hours to ride a bicycle, how many kilometers per hour do you travel by bicycle?
从甲地到乙地，小明坐汽车要用4小时，每小时行30千米．骑自行车要用6小时，骑自行车每小时行多少千米？
<gadget id="calculator">30 / 6</gadget>
<output>5</output>

<gadget id="calculator">4 * 5</gadget>
<output>20</output>

<result>20</result>