1. Lesson
Compare datas

2. Outliers A data value is an outlier if x < Q1 – 1.5(IQR) or
Statistics – numbers that characterize a data set, such as measures of center and spread.

3. Performance Task p 400
Dealer A 14 13 15 12 16 17 18
Dealer B 16 17 15 20 18 19 10
The tables list the daily car sales of two competing dealerships.

4. A. Calculate the mean, median, interquartile range (IQR), and standard deviation for each data set. Compare the measures of center for the two dealers.

5. mean
median
IQR
Standard Deviation
Dealer A
Dealer B

6. mean
median
IQR
Standard Deviation
Dealer A
14.85 15 2
1.6
Dealer B
17.3 18
2.5
2.2

7. Answer
The number of cars sold by Dealer A tends to be lower than the number of cars sold by Dealer B.
The number of cars sold by Dealer A are more consistent than the number of cars sold by Dealer B

8. B. Create a dot plot for each data set
B. Create a dot plot for each data set. Compare the distributions of the data sets.

9. Answers
The data for Dealer A show a symmetric distribution, so the number of cars sold daily by Dealer A is evenly distributed about the mean.
The data for Dealer B show a distribution skewed to the right, so during more than half of the days, car sales were greater than the mean.

10. C. Determine if there are any outliers in the data sets
C. Determine if there are any outliers in the data sets. If there are, remove the outlier and find the statistics for that data set(s). What was affected by the outliers?

11. answer Dealer A x < 14 – 1.5 (2) x > 16 + 1.5(2)
There are no values in the data set that satisfy this inequalities for x. So, there are no outliers

12. Dealer B
x < 16.5 – 1.5 (2.5) x > (2.5)
x < x > 22.75
10 is an outlier in the data set for Dealer B.
Removing the outlier increases the mean and decreases the std dev. The median is unaffected