Question 101286
 from his house to the beach in 4 hours. Back, traffic slowed his speed by 7 mi/h and the trip took 5 hours. What was his average speed (rate) in each direction?

Let t = speed to the beach
then
(t-7) = speed back from the beach
:
Distance there and back is the same so write a distance equation:
Distance = time * speed
:
from the beach dist = to the beach dist
5(t-7) = 4t
:
5t - 35 = 4t
:
5t - 4t = + 35
:
t = 35 mph to, and 28 mph back
:
:
Check solution by confirming the distances are the same:
4 * 35 = 140
:
5 * 28 = 140
:
That's pretty easy, right?