Question

The distance from Cleveland to Chicago is 345 mi. A train, traveling at 45 mi/hr leaves Chicago heading to Cleveland at the same time that another train, traveling 30 mi/hr, leaves Cleveland heading to Chicago. How far from Chicago will the two trains meet?

Answer 1

207 mi

Explanation:

The two train if they depart at the same time meet at the same time. If s=v*t then s=vA* tA and s=vB*tB so tA=tB (meeting time tm ),s=sA+sB ; s=vA*tm+vB*tm; s=(vA+vB)*tm so tm = 345mi/(45mi/hr+30mi/hr)= 4,6 hr, now is the distance A since it is how far from Chicago. s_A=v_(A*) t_m=45mi/hr*4,6hr=207mi far from Chicago