Chapter 1.3, Problem 87E

(a)

To determine

To calculate the mean of the given data.

Answer to Problem 87E

Mean = 85

Explanation of Solution

Given:

The Dataset:

86	84	91	75	78	80	74
87	76	96	82	90	98	93

Formula used:

  $\text{Mean = }\frac{\sum x_i}{n}$

Calculation:

  $\begin{array}{c}\text{Mean = }\frac{\sum x_i}{n}\\ =\frac{1190}{14}\\ =85\end{array}$

(b)

To determine

To calculate the mean of the given data when the 15^th observation is 0. Also explain the property of mean applied here.

Answer to Problem 87E

Mean = 79.33

Explanation of Solution

Formula used:

  $\text{Mean = }\frac{\sum x_i}{n}$

Calculation:

  $\begin{array}{c}\text{Mean = }\frac{\sum x_i}{n}\\ =\frac{1190}{15}\\ =79.33\end{array}$

If there is observation 0 in the dataset, then this value must be taken into the account while calculating the mean.