The distance between A and B is 180 kilometers. A car starts from A and is expected to arrive at B in 4 hours. When the car travels halfway, it takes 20 minutes to stop for repairs. If you want to arrive at B on time, you should How many kilometers do you travel?
甲、乙两地相距180千米，一辆汽车从甲地开出，预计4小时到达乙地，当汽车行驶一半路程时，停车修理用去20分钟，如果要按时到达乙地，每小时应行多少千米？
<gadget id="calculator">180 / 2</gadget>
<output>90</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 - (1/3)</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">90 / (5/3)</gadget>
<output>54</output>

<result>54</result>