Xiao Ming rides a bicycle from home to school, and rides 15km per hour, but arrives 10 minutes early, and rides 12km per hour, and then arrives 5 minutes late. How many kilometers is the distance from his home to school?
小明从家里骑自行车到学校，每小时骑15km，可早到10分钟，每小时骑12km就会迟到5分钟，问他家到学校的路程是多少千米？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/6) + (1/12)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/12) - (1/15)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/4) / (1/60)</gadget>
<output>15</output>

<result>15</result>