posted by Kelly on .
Steve mcspoke left home on his bike traveling at 18km/hr. Steve's brother set out 2 hours later , following the same route, TRAVELING 54 per hour. How long did brother have to travel to catch up with Steve?
Represent the unknown with variable.
Let x = time that Steve's brother travelled
Recall that distance is equal to speed multiplied by time. We get their distances travelled and equate them (since it's said that they followed the same route and they'll overtake at some time):
18(x + 2) = 54x
Note the Steve left two hours before his brother, thus there's +2 on his time. Solving for x,
18x + 36 = 54x
18x - 54x = -36
-36x = -36
x = 1 hour
Hope this helps~ :3