Answer:
The route across the park is 40 meter shorter than the route around its edges.
Step-by-step explanation:
We have to calculate the distance for both routes
As the route around the edges is straight, we have to find the sum of length of both edges
Let
be the distance of route around edges

Now we know that a diagonal divides a rectangle in two right angled triangles in which the diagonal is the hypotenuse.
We can use Pythagoras theorem to find the length of the diagonal
So,

In the given scenario
P = 60
B = 80
Now

In order to calculate that how much shorter is the path across the park, we have to subtract the distance across park from the distance across edges.

Hence,
The route across the park is 40 meter shorter than the route around its edges.