person walks along the sidewalk beside the railway. A passenger car comes from behind. It takes 15 seconds to pass by. The passenger car is 105 meters long and the speed is 8 meters per second. How many meters per second is the pedestrian?
某人沿着铁路边的便道步行，一列客车从身后开来，在身旁通过的时间是15秒，客车长105米，每秒速度为8米，求步行人每秒多少米？
<gadget id="calculator">15 * 8</gadget>
<output>120</output>

<gadget id="calculator">120 - 105</gadget>
<output>15</output>

<gadget id="calculator">15 / 15</gadget>
<output>1</output>

<result>1</result>