Compute Descriptive Statistics Mean, Range
Summarize a small data set by computing mean and range and explaining what each tells you.
- Read a data table: Students need to find values, labels, and units before calculating or graphing.
- Fair-test logic: Variables and controls make comparisons meaningful.
Prerequisites are inferred: pending teacher review.
Re-learn the skill with worked practice and clear examples.
Summarize a small data set by computing mean and range and explaining what each tells you.
| Trial values | 6, 8, 10, 12 |
|---|---|
| Sum | 36 |
| Mean | 36 / 4 = 9 |
| Range | 12 - 6 = 6 |
Use the mean/range table for values 6, 8, 10, 12. Which pair is correct?
Reviewed| Trial values | 6, 8, 10, 12 |
|---|---|
| Sum | 36 |
| Mean | 36 / 4 = 9 |
| Range | 12 - 6 = 6 |
- A.Mean 36; range 6
- B.Mean 6; range 9
- C.Mean 9; range 6
- D.Mean 9; range 12
Show the worked solution ▾
Answer: C. Mean 9; range 6
- Step 1: Compute mean: 36 divided by 4 equals 9.
- Step 2: Compute range: 12 minus 6 equals 6.
Why it's right: Mean is 9 and range is 6.
- A: 36 is the sum, not mean.
- B: This swaps the values.
- D: 12 is the highest value, not range.
Aligned to Biotechnology Research and Experiments · reading level ~grade 9
Five reaction times are recorded: 4, 7, 7, 9, and 13 seconds. What are the mean and the range?
Reviewed- A.Mean 7 s; range 9 s
- B.Mean 8 s; range 9 s
- C.Mean 40 s; range 9 s
- D.Mean 8 s; range 13 s
Show the worked solution ▾
Answer: B. Mean 8 s; range 9 s
- Step 1: Add the values: 4 + 7 + 7 + 9 + 13 = 40.
- Step 2: Divide by how many: 40 divided by 5 values gives a mean of 8 s.
- Step 3: Subtract for the range: 13 minus 4 gives a range of 9 s.
Why it's right: The five values sum to 40, and 40 divided by 5 is 8. The highest value 13 minus the lowest value 4 is 9.
- A: 7 is the value that appears most often, not the mean.
- C: 40 is the sum before dividing by the number of values.
- D: 13 is the highest value, not the range; the range subtracts the lowest from it.
Aligned to Biotechnology Research and Experiments · reading level ~grade 9
- In Course Launch: Safety & Lab Foundations, this skill turns class evidence into a result another person can check.
Fill these in as you work through the lesson.
- Mean (average; sum divided by count):
- Range (highest minus lowest):
- Outlier (value far from the rest):
- Data set (group of values):
Mean = divided by number of values. Range = highest value minus value.
- What is the sum of the values?
- What is the highest value?
- What is the lowest value?
For 7, 9, 10, and 14, compute the mean and range.