The road from Taizhou to Jiangyan is 18 kilometers long, and it takes about 20 minutes by motorcycle and 30 minutes by bus from Jiangyan to Taizhou. On Saturday, Dad and Xiaohua are going to play from Jiangyan to Taizhou. Dad rides a motorcycle from Taizhou, and Xiaohua takes a bus. They set off at the same time. When Dad arrives in Taizhou, how far is Xiaoming from Taizhou?
泰州到姜堰的公路长18千米，从姜堰到泰州骑摩托车大约需20分钟，乘公共汽车大约需要30分钟．星期六爸爸和小华准备从姜堰到泰州去玩，爸爸从泰州骑摩托车，小华乘公共汽车，他们同时出发，当爸爸到达泰州后，小明离泰州还有多远？
<gadget id="calculator">18 / 30</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/5) * 20</gadget>
<output>12</output>

<gadget id="calculator">18 - 12</gadget>
<output>6</output>

<result>6</result>