Last updated: October 22, 2026 · Written by the Math Made Easy math teachers
Looking for an one variable statistics test? Then this Algebra 1 test on Center, Spread and Data Displays Compared checks the whole chapter, with points for each question. This test has 8 questions worth 20 points. Allow 45 minutes and work without notes. A calculator is allowed. Show the sorted data and each summary value so that partial credit can be given.
Standards: S-ID.A.1, S-ID.A.2, S-ID.A.3 · Level: Grade 9 Algebra 1
Question 2 Five-Number Summary (3 points)
Consider the data 12, 15, 15, 18, 21, 22, 26, 30, 41.
- Give the five-number summary. (2 points)
- Find the IQR and use the 1.5 × IQR rule to decide whether 41 is an outlier. (1 point)
Question 3 Dot Plot with an Extreme Value (3 points)
The dot plot shows the goals scored by a team in 10 games.
- Find the median and the range. (1 point)
- Use the 1.5 × IQR rule to decide whether 9 is an outlier. (1 point)
- Find the mean with and without 9, and tell which of the mean and the median is affected by 9. (1 point)
Question 4 Histogram Reading (2 points)
The histogram shows the wait times of 20 customers.
- Which interval contains the median? Justify with counts. (1 point)
- Describe the shape of the distribution. (1 point)
Question 5 Compare Two Groups (3 points)
The box plots show the scores of two groups.
- Which group has the greater median? (1 point)
- Find the IQR of each group. (1 point)
- Which group is more consistent? Explain. (1 point)
Question 6 Standard Deviation by Reasoning (2 points)
Set A = {18, 20, 22} and set B = {10, 20, 30} both have a mean of 20. Without calculating, which set has the greater standard deviation? Explain.
Question 7 Missing Score (3 points)
The mean of five test scores is 84. Four of the scores are 80, 92, 76 and 88.
- Find the fifth score. (2 points)
- Find the median of the five scores. (1 point)
Question 8 Typical Salary (2 points)
The salaries (in thousands of dollars) of six employees are 38, 41, 43, 45, 46 and 140.
- Find the mean (to the nearest tenth) and the median. (1 point)
- Which better describes a typical salary? Explain. (1 point)
