There is a ring road with a length of 18 kilometers. A starts from point A of the ring road at a speed of 300 meters per minute, and drives forward along the ring road. After 24 minutes, B rides a motorcycle at a speed of 500 meters per minute. Also start from point A, send an urgent telegram to A, how many minutes will it take at the earliest?
有一条环形公路长18千米，甲骑自行车以每分钟行300米的速度从环形路的A点出发，沿环形路向前行驶，出发24分钟后，乙骑摩托车以每分钟500米的速度也从A点出发，给甲送一份加急电报，问最快需要几分钟送到？
<gadget id="calculator">18 * 1_000</gadget>
<output>18_000</output>

<gadget id="calculator">300 * 24</gadget>
<output>7_200</output>

<gadget id="calculator">18_000 - 7_200</gadget>
<output>10_800</output>

<gadget id="calculator">500 + 300</gadget>
<output>800</output>

<gadget id="calculator">10_800 / 800</gadget>
<output>27/2 = around 13.5</output>

<result>27/2 = around 13.5</result>