What is the rule of thumb when calculating the braking distance for evasive braking on a dry, even and asphalted roadway?

You answered correctly. The rule of thumb for calculating the braking distance during evasive braking (Gefahrenbremsung) on a dry, even, and asphalt surface is: take the speed in kilometers per hour, divide it by 10, multiply that number by itself, and then divide by 2. This means the formula is (speed in km/h divided by 10) squared, then divided by 2. This estimate helps you quickly calculate how much distance your car needs to come to a stop in an emergency, considering optimal dry road conditions. For example, at 100 km/h: (100/10 = 10), (10 x 10 = 100), (100/2 = 50 meters braking distance). Always use this method for quick estimation in theory questions and safe driving planning.