The mean is just the ordinary average that you learned 
back in elementary or middle school.



To find the median and the mode list the numbers in order
from smallest to largest:

3 4 5 5 5 5 5 6 6 7 7 7 8 8 9 

There are 15 numbers. 15 is an odd number of numbers, so the 
median is the one that is right in the middle of the list. 

Remember it by: "The median of a highway is in the middle."

3 4 5 5 5 5 5 6 6 7 7 7 8 8 9

The number right in the middle is 6.

(If there had been an even number of numbers, you would have 
had to average the middle two)

The mode is the number that occurs more than any other, if 
there is one, that is, the number that occurs most.

(Remember it by: the first two letters of "mode" are "mo" and
the first two letters of "more" and "most" is also "mo".

3 4 5 5 5 5 5 6 6 7 7 7 8 8 9

As you can see there are more 5's than anything else, so 5
is the mode.

Edwin