Use the table to answer the question.

This table displays the points scored by a basketball team in different games.
Points Scored
85 78 90
52 81 79
The table shows the points a basketball team scored in different games. When the outlier is removed from the data set, what happens to the mean points scored by the basketball team?

(1 point)
Responses

The mean points scored increases by 5.1.
The mean points scored increases by 5.1.

The mean points scored increases by 8.7.
The mean points scored increases by 8.7.

The mean points scored decreases by 5.1.
The mean points scored decreases by 5.1.

The mean points scored decreases by 8.7.

1 answer

To determine how the removal of the outlier affects the mean points scored, we'll first calculate the mean of the original data set and then calculate the mean after removing the outlier.

The points scored are:

  • 85
  • 78
  • 90
  • 52 (potential outlier)
  • 81
  • 79

Step 1: Calculate the mean of the original data set.

  1. Calculate the total points: \[ 85 + 78 + 90 + 52 + 81 + 79 = 465 \]

  2. Count the total number of games: \[ 6 \]

  3. Calculate the mean: \[ \text{Mean} = \frac{\text{Total Points}}{\text{Number of Games}} = \frac{465}{6} = 77.5 \]

Step 2: Identify and remove the outlier.

In this case, 52 appears to be significantly lower than the other scores and is likely the outlier.

Step 3: Calculate the mean without the outlier (52).

  1. New total points: \[ 85 + 78 + 90 + 81 + 79 = 413 \]

  2. New number of games: \[ 5 \]

  3. Calculate the new mean: \[ \text{Mean} = \frac{413}{5} = 82.6 \]

Step 4: Compare the means.

  • Original mean: 77.5
  • New mean after removing outlier: 82.6

Step 5: Calculate the change in mean. \[ 82.6 - 77.5 = 5.1 \]

Since the mean increased by 5.1 when the outlier was removed, the correct response is:

The mean points scored increases by 5.1.