Master Wang drove to Hekou to do business. He set off from Luxi at 8:30 in the morning, driving at a speed of 50 kilometers per hour, and arrived at Kaiyuan at 12:30. He travels at a high speed and arrives at his destination at 5:00 p.m. What is his average speed from Luxi to Hekou?
王师傅驾车前往河口办事，他早上8：30从泸西出发，以每小时50千米的速度行驶，12：30到达开远，用30分钟吃过早饭后，又以每小时45千米的速度行驶，在下午5时到达目的地，他从泸西到河口的平均速度是多少？
<gadget id="calculator">50 * 4</gadget>
<output>200</output>

<gadget id="calculator">45 * 4</gadget>
<output>180</output>

<gadget id="calculator">200 + 180</gadget>
<output>380</output>

<gadget id="calculator">4 + 4</gadget>
<output>8</output>

<gadget id="calculator">380 / 8</gadget>
<output>95/2 = around 47.5</output>

<result>95/2 = around 47.5</result>