解:设甲每秒跑x(m)乙每秒跑y(m)30x+30y=40080y-80x=400240x+240y=3200-240x+240y=1200480y=4400y=55/6x=25/6
400/30=(X+Y)400/(80)=(X-Y)X=55/6 Y=25/6甲速度25/6 乙速度X=55/6
你真懒,超easy你直接罢做就好了还来问