Delete the 5 from the data numbers given for Example 1 and then do the following with the resulting data.

Find the mean using the definition, as in Example 3.

Data from Example 3

The mean of the numbers given in Example 1 is determined by finding the sum of all the numbers and dividing by 15. Therefore, by letting x̄(read as “x bar”) represent the mean, we have

Thus, the mean is 5.5. (The mean is usually calculated to one more decimal place than was present in the original data.)

TR X || = 5+2 +6+4+7+4+7+2+8+9+4+11+9+1+3 15 sum of values 5.5 number of values