Dongdong walks to school, walking 75 meters per minute. After Dongdong left home for 12 minutes, his father found that he had forgotten his pencil case, so he immediately rode a bicycle to chase him, walking 375 meters per minute, and begged his father to catch up with Dongdong. separated.
冬冬步行上学，每分钟行75米，冬冬离家12分钟后，爸爸发现他忘了带文具盒，马上骑自行车去追，每分钟行375米，求爸爸追上冬冬所需要的时间隔．
<gadget id="calculator">75 * 12</gadget>
<output>900</output>

<gadget id="calculator">375 - 75</gadget>
<output>300</output>

<gadget id="calculator">900 / 300</gadget>
<output>3</output>

<result>3</result>