James B. answered 06/04/16
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So think of the diagram as the coordinate plane.
By number, starting with 1 and ending at 7, I have diagrammed Lisa's path.
Since it is a 2 mile track, that means when she is on the circular path (Quadrants 1 & 4)
she walks 1/2 mile in each of those 2 quadrants
The distance around the track is 2 miles. That is equivalent to the circumference of the circular track.
We us this info to determine the diameter of the circle.
pi • diameter = 2 miles
diameter = 2 / pi
so since she takes a shortcut from point 3 to 4 to 5, that distance represents the diameter
of the circle.
So her total distance is
from 1 to 2 to 3 => .5 miles
from 3 to 4 to 5 => 2/pi miles = .63662 milrs
from 5 to 6 to 7 => .5 miles
Total distance 1.63662 miles = 1.6 miles
3
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----------------------4---------------------- 1 & 7
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5