Xiao Ming rides a bicycle, the speed of driving uphill is 8 km/h, the speed of driving downhill is 10 km/h, and the speed of driving on flat road is 9 km/h. One day Xiao Ming set off from home for an outing by bike. He spent the same amount of time on the way uphill, downhill, and flat road on the way out, and it took him 15 minutes longer on the way back than the way out. The destination of the outing How many kilometers is the distance from Xiao Ming's house?
小明骑自行车，上坡行驶的速度是8千米/时，下坡行驶的速度是10千米/时，平路行驶的速度是9千米/时．有一天小明从家骑车出发去郊游，他在去程中，上坡，下坡，平路所花费的时间相等，而他在回程时所花费的时间比去程多15分钟，郊游目的地与小明家的距离为多少千米？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">10 / 8</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">8 / 8</gadget>
<output>1</output>

<gadget id="calculator">(5/4) - 1</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/4) / (1/4)</gadget>
<output>1</output>

<gadget id="calculator">8 * 1</gadget>
<output>8</output>

<gadget id="calculator">10 * 1</gadget>
<output>10</output>

<gadget id="calculator">9 * 1</gadget>
<output>9</output>

<gadget id="calculator">8 + 10 + 9</gadget>
<output>27</output>

<result>27</result>