On a boulevard, there is a traffic light every 900 meters. All the traffic lights are changed repeatedly according to the time cycle of green light for 30 seconds, yellow light for 5 seconds and red light for 25 seconds. After a car passes the first traffic light, how many kilometers per hour does it travel at, and can it encounter green lights at all traffic light intersections on this avenue?
在一条大道上，每隔900米有一个红绿灯．所有的红绿灯都按绿灯30秒、黄灯5秒、红灯25秒的时间周期重复变换．一辆汽车通过第一个红绿灯以后，它以每小时多少千米的速度行驶，可以在这条大道上所有的红绿灯路口都遇到绿灯？
<gadget id="calculator">30 + 5 + 25</gadget>
<output>60</output>

<gadget id="calculator">1 / 60</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">0.9 / (1/60)</gadget>
<output>54</output>

<result>54</result>