Simple Root

Road Sign Math is a particularly difficult game to play with signs that have only two numbers (remember, by the rules in mileage signs you are not allowed to use any road numbers, only distance indicators). The lack of a third (or more) number requires you to use math functions that requires only a single number. This sign is one of the most simplistic of these.



The math is obvious...

$$\sqrt 4 = 2$$

This sign was discovered on a rainy day in Iowa on highway 18 westbound just before mile marker 182.