Ride a motorcycle from home to the train station to catch the train. If you travel 30 kilometers per hour, you will be 15 minutes early; if you travel 20 kilometers per hour, you will be 5 minutes late. If you plan to arrive 5 minutes earlier, what should be the speed of the motorcycle?
从家里骑摩托车到火车站赶乘火车．如果每小时行30千米，那么早到15分钟；如果每小时行20千米，则迟到5分钟．如果打算提前5分钟到，摩托车的速度应是多少．
<gadget id="calculator">5 / 60</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">15 / 60</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/12) + (1/4)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/20) - (1/30)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/3) / (1/60) / 30</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(1/4) - (1/12)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(2/3) + (1/6)</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">(1/3) / (1/60) / (5/6)</gadget>
<output>24</output>

<result>24</result>