Question

Use the data to answer the following questions: 68, 63, 67, 66, 65, 87, 69, 61, 86, 82, 28

Answer 1

Rewrite given data in increasing order:

28, 61, 63, 65, 66, 67, 68, 69, 82, 86, 87

An outlier is an observation that lies an abnormal distance from other values in a random sample from a population.  As you can see that number 28 lies an abnormal distance from other values.

Answer A: 28

The mean (or average) of a set of data values is the sum of all of the data values divided by the number of data values.

$\text{mean with outlier}=\dfrac{28+61+63+65+66+67+68+69+82+86+87}{11}=\dfrac{742}{11}=67.454545...\approx67.45.$

Answer B: 67.45

$\text{mean without outlier}=\dfrac{61+63+65+66+67+68+69+82+86+87}{11}=\dfrac{742}{10}=71.4.$

Answer C: 71.4