Hint: Think about d = rt, which means that t = d/r. Think about each section of her walk, what is the distance and the rate. You know that the total time is 5 hours, so you know the sum of the times from each section must be 5.

Let Level distance = L and hill distance = H. Add the times it took for each section of the walk:

L/4 + H /3 + H/6 + L/4 = 5

The LCD of this is 12 from our LCD Calculator

__Multiply each side through by our LCD of 12__

3L + 4H + 2H + 3L = 60

__Combine like terms:__

6L + 6H = 60

__Divide each side by 3:__

2L + 2H = 20

The woman walked

**20 miles**