A train travels at a speed of 65 kilometers per hour for 3 hours, and then at a speed of 80 kilometers per hour for 2 hours. How many kilometers per hour does it travel on average?
一列火车，先以每小时65千米的速度行3小时，又以每小时80千米的速度行了2小时，平均每小时行多少千米？
<gadget id="calculator">65 * 3</gadget>
<output>195</output>

<gadget id="calculator">80 * 2</gadget>
<output>160</output>

<gadget id="calculator">195 + 160</gadget>
<output>355</output>

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

<gadget id="calculator">355 / 5</gadget>
<output>71</output>

<result>71</result>