A man walked diagonally across a square lot. Approximately, what was the percent saved by not walking along the edges?

Let the side of the square(ABCD) be x meters.

Then, AB + BC = 2x metres.

AC =  $2x$ = (1.41x) m.

Saving on 2x metres = (0.59x) m.

Saving % = $\frac{0.59x}{2x}*100$ = 30% (approx)