There are two roads from a certain county to the provincial capital: one is an expressway and the other is an ordinary road. If you take a car on a highway, you can travel 80 kilometers per hour, and the distance is 160 kilometers; if you take a car on an ordinary road, you can travel 40 kilometers per hour, and the distance is 120 kilometers. Which way to go to save time? How much time can be saved?
从某县城到省城有两条公路：一条为高速公路，另一条为普通公路．如果乘车走高速公路，每小时可行80千米，距离为160千米；如果乘车走普通公路，每小时行40千米，距离为120千米．走哪条路节约时间？可以节约多少时间？
<gadget id="calculator">120 / 40</gadget>
<output>3</output>

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

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<result>1</result>