A tourist bus travels on the plains and mountains for 2 hours, 50 kilometers in one hour on the plains, 30 kilometers in an hour in the mountains, and finally reaches the top of the mountain. How much is the distance?
一辆旅游车在平原和山区个行驶2小时，在平原一小时行驶50千米，在山区一小时行驶30千米，最后到达山顶，这段路程大约有多少？
<gadget id="calculator">50 + 30</gadget>
<output>80</output>

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

<result>160</result>