A highway is 210 kilometers long, and a car travels 135 kilometers in 3 hours. According to this calculation, how many hours are left?
一条公路全长210千米，一辆汽车3小时行135千米，照这样计算，剩下的还要行多少小时？
<gadget id="calculator">210 - 135</gadget>
<output>75</output>

<gadget id="calculator">135 / 3</gadget>
<output>45</output>

<gadget id="calculator">75 / 45</gadget>
<output>5/3 = around 1.666667</output>

<result>5/3 = around 1.666667</result>