Xiao Li ran a lap on the 400-meter circular runway of Beijiang Middle School. It is known that he ran fast at first, and then slowed down. He ran 6 meters per second in the first half of the time and 4 meters per second in the second half of the time. Then , How many meters did Xiao Li run in the second half of the time?
小李在北江中学的400米环形跑道上跑了一圈，已知他开始跑得较快，后来较慢，在前一半时间里每秒跑6米，后一半时间里每秒4米，那么，小李在后一半时间里一共跑了多少米．
<gadget id="calculator">40 * 4</gadget>
<output>160</output>

<result>160</result>