A and B start at the same time at the same time and run along a circular track at a constant speed. If B's speed is 2.5 times that of A when starting out, when B catches up with A for the first time, A's speed will immediately increase by 25%, while B's speed will immediately decrease by 20%, and the place where B catches up with A for the first time is the same as The place where A catches up with A for the second time is 100 meters apart, so how many meters is the circumference of this circular runway?
甲、乙两人同时同地同向出发，沿环形跑道匀速跑步．如果出发时乙的速度是甲的2.5倍，当乙第一次追上甲时，甲的速度立即提高25%，而乙的速度立即减少20%，并且乙第一次追上甲的地点与第二次追上甲的地点相距100米，那么这条环形跑道的周长是多少米？
<result>300</result>