Question

Jina drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 6 hours. When Jina drove home, there was no traffic and the trip only took

4 hours. If her average rate was 22 miles per hour faster on the trip home, how far away does Jina live from the mountains?
Do not do any rounding.

Answer 1

I need a clear understanding....

Answer 2

264 miles

Explanation:

Using the relation ...

distance = speed · time

we can rearrange to get ...

speed = distance/time

We can choose to let d represent the distance we want to find. Then Jina's speed going to the mountains is d/6. Her speed coming home is then d/6+22. It takes Jina 4 hours at that speed to cover the same distance, so we have ...

d = 4(d/6 +22)

d = 2/3d +88 . . . . eliminate parentheses

1/3d = 88 . . . . . . . subtract 2/3d

d = 264 . . . . . . . . . multiply by 3

Jina lives 264 miles from the mountains.