Start with the type of picture drawn by EP -- respresenting the unrolled cylinder as a rectangle.
Place this rectangle upon a coordinate grid with the
-- bottom-left corner at (0,0)
-- bottom-right corner at (24,0)
-- top-left corner at (0,10)
-- top-right corner at (24,10)
-- fly at (24,4)
-- drop of honey at (12,7)
Moving from fly to honey will be the distance sqrt(122 + 32) = sqrt(153)
[you can draw a right triangle and use the Pythagorean Theorem or use the distance formula]