person rides a bicycle from home to school. If you travel 15 kilometers per hour, you can arrive 15 minutes earlier than the scheduled time; if you travel 9 kilometers per hour, you can arrive 15 minutes later than the scheduled time; how many kilometers is the distance from home to school?
某人从家里骑自行车到学校．若每小时行15千米，可比预定时间早到15分钟；若每小时行9千米，可比预定时间晚到15分钟；求从家里到学校的路程有多少千米？
<gadget id="calculator">15 / 60</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">15 * (1/4)</gadget>
<output>15/4 = around 3.75</output>

<gadget id="calculator">9 * (1/4)</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">(15/4) + (9/4)</gadget>
<output>6</output>

<gadget id="calculator">15 - 9</gadget>
<output>6</output>

<gadget id="calculator">6 / 6</gadget>
<output>1</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">15 * (3/4)</gadget>
<output>45/4 = around 11.25</output>

<result>45/4 = around 11.25</result>