Statistics: Range and Outliers
Finding spread and spotting unusual data values
Statistics: Range and Outliers
Finding spread and spotting unusual data values
Statistics - Grade 4-5
- 1
The numbers of books read by five students are 4, 6, 8, 5, and 7. What is the range of the data set?
Range means greatest value minus least value.
The range is 4 because the greatest value is 8 and the least value is 4, so 8 - 4 = 4. - 2
The heights of six plants in centimeters are 12, 14, 13, 15, 50, and 14. Which value is an outlier? Explain why.
Look for the number that is far away from most of the other numbers.
The outlier is 50 because it is much greater than the other plant heights, which are all between 12 and 15 centimeters. - 3
A soccer team scored these points in six games: 2, 3, 1, 4, 2, and 3. Find the range.
The range is 3 because the greatest score is 4 and the least score is 1, so 4 - 1 = 3. - 4
The times, in minutes, for students to finish a puzzle are 9, 10, 11, 12, 10, and 45. What is the outlier, and how would removing it change the range?
Find the range with all values, then find the range without the unusual value.
The outlier is 45 because it is much larger than the other times. With 45 included, the range is 45 - 9 = 36 minutes. Without 45, the range is 12 - 9 = 3 minutes, so removing it makes the range much smaller. - 5
The daily high temperatures in degrees Fahrenheit were 70, 72, 69, 71, 73, and 72. Is there an outlier? Explain your answer.
There is no outlier because all the temperatures are close together, from 69 to 73 degrees. - 6
Mia counted the number of jump ropes in different bins: 8, 9, 7, 8, 30, and 9. Find the range of the data set and name the outlier.
The same data set can have a range and an outlier.
The range is 23 because 30 - 7 = 23. The outlier is 30 because it is much larger than the other numbers, which are between 7 and 9. - 7
A class recorded the number of sunny days each month: 20, 18, 19, 21, 17, and 20. What is the range?
The range is 4 because the greatest value is 21 and the least value is 17, so 21 - 17 = 4. - 8
Look at this data set of pet weights in pounds: 9, 10, 11, 10, 42, and 12. Which number is an outlier? Explain what makes it unusual.
Compare each number to the group of numbers that are close together.
The outlier is 42 because most of the pet weights are between 9 and 12 pounds, but 42 pounds is far above the rest. - 9
The ages of cousins at a picnic are 6, 7, 8, 9, 7, and 8. Find the range and tell whether there is an outlier.
The range is 3 because 9 - 6 = 3. There is no outlier because all the ages are close together. - 10
The scores on a 20-point quiz were 16, 17, 18, 17, 19, and 3. What is the outlier, and what is the range?
An outlier can be much smaller than the other values.
The outlier is 3 because it is much lower than the other scores. The range is 16 because the greatest score is 19 and the least score is 3, so 19 - 3 = 16. - 11
A store sold these numbers of notebooks each day: 24, 26, 25, 27, 23, 25, and 26. Find the range.
The range is 4 because the greatest value is 27 and the least value is 23, so 27 - 23 = 4. - 12
The number of minutes spent reading each night were 22, 25, 24, 23, 80, and 25. How does the outlier affect the range?
Outliers often make the range bigger because they change the greatest or least value.
The outlier is 80 because it is much larger than the other values. It makes the range much larger, since the range with 80 is 80 - 22 = 58 minutes, but without 80 the range is 25 - 22 = 3 minutes. - 13
The lengths of pencils in centimeters are 14, 13, 15, 14, 2, and 13. Identify the outlier and find the range.
The outlier is 2 because it is much shorter than the other pencil lengths. The range is 13 because 15 - 2 = 13. - 14
A teacher wrote two data sets on the board. Set A is 5, 6, 7, 8, 9. Set B is 5, 6, 7, 8, 30. Which set has the greater range, and why?
Find the range for each set before comparing them.
Set B has the greater range. Set A has a range of 9 - 5 = 4, while Set B has a range of 30 - 5 = 25 because 30 is much larger than the other values. - 15
The number of stickers collected by seven students are 12, 15, 14, 13, 16, 15, and 14. Find the range and explain whether the data set has an outlier.
If no value is far away from the rest, there may not be an outlier.
The range is 4 because the greatest value is 16 and the least value is 12, so 16 - 12 = 4. The data set does not have an outlier because all the numbers are close together.