Question 389977
At 6:00 am, the Eilerman family left for Christmas vacation and drove south
 at an average speed of 40 mph.
 Their friends, the Knapke's, left two hours later and traveled the same route
 at an average speed of 55 mph.
 At what time could the Knapke's expect to overtake the Eilerman's?
:
Let t = K family's travel time
then
(t+2) = E family's travel time
:
When K overtakes E, they will have traveled the same distance
Write a dist equation: dist = speed * time
:
K's dist = E's dist
55t = 40(t+2)
55t = 40t + 80
55t - 40t = 80
15t = 80
t = {{{80/15}}}
t = 5{{{1/3}}} hrs or 5 hrs 20 min; K's travel time
:
K started at 8:00 AM therefore, they will catch E at 1:20 PM
:
:
Check solution by finding the distances
55 * 5.33 = 293.33 mi
40 * 7.33 = 293.33 mi