So this will always give you a positive value. So let's take this example and let's use these two values to find our average. So BRMs is equal to 60 mph squared plus negative 60 mph squared. This gives you 3600 plus negative canceled. So 3600 gives you 7200 divided by two and square root, that gives you 60 mph. So you see, once again, that the purpose of the route means square is to take away those negative signs and just give you the magnitude.