<PRE><B>Question 627513</B>
A horse can travel at the rate of 5miles per hour for the first two hours of the trip. 
After the first two hours the horse&#39;s speed drops to 3 miles per hour.
 How many hours will it take the horse to travel 20 miles?
:
let t = total time for the trip
then
(t-2) = time at 3 mph (1st two hrs were at 5 mph)
:
Write a distance equation: dist = speed * time
:
Dist at 5 mph + Dist at 3 mph = 20 miles
5(2) + 3(t-2) = 20
10 + 3t - 6 = 20
3t + 4 = 20
3t = 20-4
3t = 16
t = 16/3
t = 5{{{1/3}}} hrs for the trip
:
:
Check this
5(2) + 3(3.333) = 20 mi</PRE>