mary leaves her house at noon , traveling in her car at 45 mi/h . Later , mary's brother joe leaves their house and travels the same direction at 60 mi/h . if joe leaves at 2:00 p.m. , at what time will he catch up with mary ?

Question

0bucchr · Answer

simultaneous equations necessary:
they will meet at a certain time.
velocity = dist/time
time = dist/vel
when joe leave mary has gone 90m (45m/h*2h)
djoe = dmary + 90
time = time
dj/60 = dm/45 
(dm + 90)/60 = dm/45
dm = 270
t = 270/60 = 4.5h