Since the problem is given all the total walking distance, the first thing we are going to do is find the total distance in the map:


Now that we have the distance in the map, we can establish a ratio between the walking distance and the distance in the map:

We can conclude that each inch the map represents 0.5 miles of walking distance.
The answer is 9/10
the denominator is on the bottom
-8(3)(12)
2(12)(-4)
-8(36)
2(-48)
-288
-96
3