This is why you rarely see bats hanging in an attic in the winter-it is just too cold for survival. People who have a colony of bats in their home often describe a scratching sound or occasionally get a bat inside their home. We believe that the bats move around and adjust their position based upon the temperature.
The mean of a set of numbers is their average. You find the average of a set of numbers by adding them up and dividing by the number of numbers you have. So, the mean of 3,4,6,9, and 3 is: 3 + 4 + 6 + 9 + 3 25 ----------------- = -- = 5 5 5.
In fact even in mathematics there are different averages or means and this one is more properly called the arithmetic mean. The quantity obtained by adding the largest and smallest values and dividing by 2, statisticians call the midrange. There are times however that this is called the mean.