Question

Ivan drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took
8
hours. When Ivan drove home, there was no traffic and the trip only took
5
hours. If his average rate was
21
miles per hour faster on the trip home, how far away does Ivan live from the mountains?

Answer 1

I believe it would be 105 mi

Answer 2

let onward speed = x mph, then distance = 7x
return speed = (x+18) mph, (same) distance = 5(x+18)
equating the two,
7x = 5(x+18)
2x = 90 ==> x = 45 mph
so distance = 7*45 = 315 miles

Answer 3

its 315 miles!

Answer 4

no that was wrong its 280

Answer 5

how did you get 280??