A motorcycle travels 60 kilometers at an average speed of 20 kilometers per hour. On the way home, its average speed is 30 kilometers per hour. What is the average speed of the motorcycle during the entire round trip?
一辆摩托车以平均每小时20千米的速度行完了60千米的旅程．在回家的路上，它的平均速度是每小时30千米．问摩托车在整个来回的旅程中，平均速度是多少？
<gadget id="calculator">60 * 2</gadget>
<output>120</output>

<gadget id="calculator">60 / 20</gadget>
<output>3</output>

<gadget id="calculator">60 / 30</gadget>
<output>2</output>

<gadget id="calculator">3 + 2</gadget>
<output>5</output>

<gadget id="calculator">120 / 5</gadget>
<output>24</output>

<result>24</result>