The traffic lights at an intersection, the yellow light is on for 3 seconds, the green light is on for 9 seconds, and the red light is on for 24 seconds, then what is the probability that the green light is on at a certain moment
某十字路口的交通信号灯，黄灯亮3秒，绿灯亮9秒，红灯亮24秒，那么某一时刻亮绿灯的可能性为多少
<gadget id="calculator">3 + 9 + 24</gadget>
<output>36</output>

<gadget id="calculator">9 / 36</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>