A tourist bus drove for 4 hours on the plains and mountains respectively, and arrived at the destination. The speed on the plain is 72 km/h, and the speed on the mountain is 35 km/h. How far did you travel in total to reach your destination?
一辆旅游车在平原和山区各行驶了4小时，到达了目的地．在平原的速度是72千米/时，在山区的速度是35千米/时．到达目的地时总共行驶了多远的路程？
<gadget id="calculator">72 + 35</gadget>
<output>107</output>

<gadget id="calculator">107 * 4</gadget>
<output>428</output>

<result>428</result>