Two cars, fast and slow, are running opposite each other from A and B at the same time. After 5 hours, the two cars meet at a distance of 40 kilometers from the midpoint. After the meeting, the two cars still drive at the same speed, and the express train takes another 4 hours to reach B. How many kilometers is the distance between A and B?
快、慢两车同时从甲乙两地相对而行，经过5小时在离中点40千米处两车相遇，相遇后两车仍以原速行驶，快车又用4小时到达乙地．甲乙两地的路程是多少千米？
<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">80 / 5 / (1/5)</gadget>
<output>80</output>

<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">80 * 9</gadget>
<output>720</output>

<result>720</result>