1
The 8 eyelets for the lace of a sneaker all lie on a rectangle, four
equally spaced on each of the longer sides. The rectangle has a width of
50 mm and a length of 80 mm. There is one eyelet at each vertex of the
rectangle. The lace itself must pass between the vertex eyelets along a
width side of the rectangle and then crisscross between successive
eyelets until it reaches the two eyelets at the other width side of the
rectangle as shown. After passing through these final eyelets, each of
the ends of the lace must extend at least 200 mm farther to allow a knot
to be tied. Find the minimum length of the lace in millimeters.