Question

Dale drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 7 hours. When Dale drove home, there was no traffic and the trip only took 5 hours. If his average rate was 18 miles per hour faster on the trip home, how far away does Dale live from the mountains? Do not do any rounding.

Answer 1

Use a system of equations:

For his trip on the way there:
D = 7*s

For his trip on the way home you have:
D = 5*(s+18)

use substitution to solve