Chapter 1.3, Problem 88E

(a)

To determine

To calculate the mean of the given data.

Answer to Problem 88E

Mean = 81.21

Explanation of Solution

Given:

The Dataset:

71	104	76	88	78	71	68	86	70	90
74	76	69	68	88	96	68	82	120

Formula used:

  $\text{Mean = }\frac{\sum x_i}{n}$

Calculation:

  $\begin{array}{c}\text{Mean = }\frac{\sum x_i}{n}\\ =\frac{1543}{19}\\ =81.21\end{array}$

(b)

To determine

To calculate the mean of the given data after removing the observation 120 from the dataset.

Answer to Problem 88E

Mean =

Explanation of Solution

Formula used:

  $\text{Mean = }\frac{\sum x_i}{n}$

Calculation:

  $\begin{array}{c}\text{Mean = }\frac{\sum x_i}{n}\\ =\frac{1423}{18}\\ =79.06\end{array}$

The mean value is not resistant to the extreme value it gets affected due to the extreme values and also we should not include the values of the observations which might be affected due to some confounding variables.