There are two people, A and B. A finds B walking in the opposite direction in the car. After 40 seconds, A gets out of the car and chases B. If he travels twice as fast as B, but 0.8 times slower than the car. How long does it take for A to catch up with B?
有甲、乙两人，甲在汽车上发现乙向相反的方向走去，40秒钟后甲下车去追赶乙，如果他行的速度比乙快一倍，但比汽车速度慢0.8倍．甲追上乙需要多少时间．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">0.8 + (1/2)</gadget>
<output>1.3</output>

<gadget id="calculator">1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1.3 / (1/2)</gadget>
<output>2.6</output>

<gadget id="calculator">40 * 2.6</gadget>
<output>104</output>

<result>104</result>