The Quadrilateral is JKLM,
let

be the midpoints of JK, KL, LM and JM respectively.
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Given any 2 point P(m,n) and Q(k,l),<span>
the coordinates of the midpoint of the line
segment PQ are given by the formula:
, </span>
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thus the coordinates of points 
are as follows:

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The distance between any 2 points P(a,b) and
Q(c,d) in the coordinate plane, is given by the formula:<span>
</span>
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thus the distances connecting the opposite entrances can be calculated as follows:


Thus the total distance of the paths joining the opposite entrances is
5+5.39 units = 50 m + 53.9 m = 104 m (rounded to the nearest meter)
Answer: 104 m