Question

Eric drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 7 hours. When Eric drove home, there was no traffic and the trip only took 4 hours. If this average rate was 27 miles per hour faster on the trip home, how far away does Eric live from the mountains. Do not do any rounding.

Answer 1

Eric drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 7 hours.When Eric drove home, there was no traffic and the trip only took 4 hours.If his average rate was 27 miles per hour faster on the trip home, how far away does Eric live from the mountains?
let s = his speed in trafficthen (s+27) = his speed coming homeWrite a distance equation; dist = time * speedthe dist there and back was the same, therefore7s = 4(s+27)7s = 4s + 1087s - 4s = 1084s = 108s = 108/4 s = 27 mph in traffic"how far away does Eric live from the mountains?"7 * 27 = 189 miles