Outlier Warmup 3

The scatter plot below shows John’s scores in the seven math and science chapter tests this semester. Which statement best describes the association between his math and science test scores?

• positive, linear, no outliers

• negative, linear, no outliers

• positive, linear, one outlier at (63, 99)

• negative, linear, one outlier at (99, 63)

• positive, linear, one outlier at (99, 63)

Answer explanation

John's scores show a positive linear relationship, indicating that as his math scores increase, his science scores also tend to increase. The point (63, 99) is an outlier, as it deviates from the overall trend.

A point far away from the other data points is considered a(n) ____?

• cluster

• scatter plot

• outlier

• variable

Answer explanation

A point far away from other data points is called an outlier. Outliers are values that differ significantly from the majority of the data, indicating they may be anomalies or errors.

What does "mean" mean?

• average

• middle

• repeats the most

• variation

Answer explanation

The term "mean" refers to the average value in a set of numbers, calculated by dividing the sum of all values by the number of values. Therefore, the correct answer is "average."

How do you find the range?

• order least to greatest, then slash from each side until you reach the middle

• add the numbers in your data set, then divide by the amount you added

• look for the number that repeats the most

• highest number minus the lowest number

Answer explanation

To find the range, subtract the lowest number in your data set from the highest number. This gives you the difference, which represents the range of the data.

Find the outlier in the set of data:
4, 11.6, 50, 23, 20.1, 19, 29, 12.7, 8, 23, 57.5

• 57.5

• 50, 57.5

• 4, 50, 57.5

• None

Answer explanation

The outlier in the data set is 57.5, as it is significantly higher than the other values, which range from 4 to 50. The other numbers are more closely grouped, making 57.5 the only clear outlier.

Using the information below, identify which of the following is NOT an outlier:
Q1 = 53
Q2 = 55
Q3=61

• 73

• 40

• 80

• 73.5

Answer explanation

To identify outliers, calculate the IQR: IQR = Q3 - Q1 = 8. Outliers are values < Q1 - 1.5*IQR or > Q3 + 1.5*IQR. Here, 73 is within the range (53 - 12, 61 + 12), while 40, 73.5, and 80 are outliers.