Xiao Ming leaves school at five o'clock every day, and his father rides a bicycle to pick him up at the school gate. One day Xiao Ming leaves school at four o'clock, and he walks home at a speed of 3,000 meters per hour. On the way, he meets his father. They go home 20 minutes earlier than usual. May I ask? What is Dad's speed?
小明每天五点放学，爸爸骑车到校门去接他，一天小明四点放学，他以每小时3000米的速度往家走，在路途中碰到爸爸，他们比平时提前20分钟回家，请问爸爸的速度是多少？
<gadget id="calculator">5 - 4</gadget>
<output>1</output>

<gadget id="calculator">2 / 20</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">3_000 * 1 * (1/10)</gadget>
<output>300</output>

<result>300</result>