Answer :
The total time for the trip is:
T = 3mi*( 3/2x).
Where x is the rate at which she comes home.
How to find the time for the total trip?
Remember the relation:
distance = rate*time.
We know that the distance is 3 miles (done twice).
First, the rate is 2x and then the rate is x, then the time it took the first half is:
t = 3mi/2x
And for the coming back:
t = 3mi/x
Then the total time for the trip is:
T = 3mi/2x + 3mi/x = 3mi( 1/2x + 1/x) = 3mi*( 3/2x).
If you want to learn about rates:
https://brainly.com/question/605631
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