SOLUTION: Gerry left at 4:00pm. traveling at 55 mph. Joe left one hour later and passed gerry at 9:00pm. How fast was Joe traveling?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Gerry left at 4:00pm. traveling at 55 mph. Joe left one hour later and passed gerry at 9:00pm. How fast was Joe traveling?      Log On


   

Question 1069504: Gerry left at 4:00pm. traveling at 55 mph. Joe left one hour later and passed gerry at 9:00pm. How fast was Joe traveling?
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Time is in quantity, not shown as time on the clock:

           SPEED      TIME      DISTANCE
Gerry       55         5          d
Joe          r        5-1=4       d

Gerry's data easily gives the distance when Joe passed him.
d=55%2A5
highlight%28d=275%2Amiles%29

Joe's speed can be found now knowing d.
r%2A4=d
r=d%2F4
r=275%2F4
highlight%28r=69%28miles%2Fhour%29%29