Grade 9 Data & Statistics Worksheets
Free printable data & statistics practice for Grade 9 students. Generate problems, solve them on screen or paper, and download as PDF.
Practice Worksheet
Grade 9 Data & Statistics Practice
Solve each problem. Show your work.
- 1.Classify the correlation shown by (1, 14), (2, 11), (3, 9), (4, 6), (5, 3): _____
- 2.A school surveys only students leaving the gym about weekly exercise. Identify the sampling problem: _____
- 3.Find the median and range of 2, 3, 5, 8, 12: _____
- 4.Classify the correlation shown by (1, 5), (2, 7), (3, 10), (4, 12), (5, 15): _____
- 5.A school surveys only students leaving the gym about weekly exercise during team practice. Identify the sampling problem: _____
- 6.Find the median and range of 3, 4, 6, 9, 13: _____
Show answer key
- Question 1: strong negative correlation
- Question 2: selection bias; the sample is not representative
- Question 3: median 5; range 10
- Question 4: strong positive correlation
- Question 5: selection bias; the sample is not representative
- Question 6: median 6; range 10
Free Practice Worksheets
Print, solve on paper, then upload a photo for instant AI grading and feedback.
Build confidence with approachable problems
Solve each problem. Take your time.
- 1.Given a scatter plot with points (1, 2), (2, 4), and (3, 6), determine if the correlation is positive, negative, or zero.
- 2.A scatter plot shows points distributed randomly with no discernible pattern. What is the correlation coefficient (r) likely close to: 1, 0, or -1?
- 3.A survey of 50 students out of 1000 is taken to predict school lunch preferences. Is this a sample or a census?
- 4.If a line of best fit for a scatter plot has the equation y = 2x + 1, calculate the predicted y-value when x = 4.
- 5.Identify the independent variable in a scatter plot comparing 'Hours Spent Studying' (x) and 'Test Score' (y).
- 6.A survey asks, 'Don't you agree that this new policy is unfair?' Is this an example of an unbiased or a biased question?
Full range of grade expectations
Solve each problem. Show your work.
- 1.A researcher collects data on the number of hours students spend studying per week (x) and their final exam scores (y). The resulting scatter plot shows a strong, positive linear correlation. If the line of best fit is y = 4.5x + 62, predict the exam score for a student who studies 8 hours per week.
- 2.A survey company wants to determine the most popular hobby among teenagers in a city of 500,000. They decide to survey 100 students standing outside a local video game store. Identify the sampling bias in this method and explain why it might lead to non-representative data.
- 3.Data regarding the average price of a house (y) in thousands of dollars over time (x) in years since 2010 yields a correlation coefficient (r) of -0.85. Interpret the meaning of this correlation in the context of the housing market.
- 4.A news outlet publishes a graph showing that ice cream sales and forest fire occurrences are positively correlated. Explain why this does not imply that eating ice cream causes forest fires. Identify a potential 'lurking' or confounding variable that could influence both sets of data.
- 5.A company claims that 90% of their customers are satisfied based on a survey of 20 people who called their help desk. Is this a reliable sample to represent the entire population of customers? Discuss the ethical considerations of using this data to market the product as '90% satisfaction guaranteed'.
- 6.Given a scatter plot of data where the x-values are (2, 4, 6, 8) and y-values are (15, 25, 35, 45), determine the slope of the line of best fit and explain if the correlation is perfect, strong, or weak.
What Your Child Will Learn
The Grade 9 data strand introduces students to the full cycle of statistical investigation: posing a question, collecting or sourcing data, organizing it, and drawing defensible conclusions. Students construct and interpret scatter plots, identify whether a relationship looks linear or non-linear, and describe correlation as strong, weak, positive, or negative — while learning the critical distinction that correlation does not imply causation.
Students draw a line of best fit by eye, use it to make predictions (interpolation and extrapolation), and evaluate how reliable those predictions are, especially when extrapolating far beyond the collected data. The unit also addresses bias in data collection and representation, asking students to critique graphs and surveys that mislead through scale manipulation, small sample sizes, or leading questions.
This strand builds directly on data literacy from earlier grades but adds a layer of critical evaluation appropriate for teenagers who are increasingly exposed to statistics in the news and on social media. It also lays groundwork for the probability and statistics work students may encounter again in Grade 12 Data Management.
Skills Covered
- Constructing and interpreting scatter plots
- Describing correlation (strength and direction) between variables
- Drawing a line of best fit and using it to interpolate and extrapolate
- Distinguishing correlation from causation
- Identifying bias in data collection, sampling, and graph design
- Summarizing and communicating conclusions from a data set
Curriculum Aligned: Part of the de-streamed Grade 9 math course (MTH1W in Ontario), covering the data strand focused on statistical investigation and critical data literacy.
Parent Tip: You don't need to remember the statistics to help here — ask your teen to show you a scatter plot from their homework and explain what story it tells. If they can describe the trend and flag anything suspicious about how the data was collected, they've grasped the point of the unit even if the calculations feel rusty to you.
What your child will practice
- Scatter Plots and CorrelationCreate scatter plots to examine relationships between two variables and identify correlation.
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Check my workFrequently Asked Questions
How often should my child practice data & statistics?
Short daily practice sessions of 10-15 minutes are more effective than long weekly sessions. Consistency builds lasting understanding.
How do I know if my child is at the right level for these worksheets?
If your child can complete about 70% of the problems correctly, the level is appropriate. If it's too easy or too hard, try an adjacent grade level.
Can I use these worksheets for homeschool?
Yes. The worksheets align with standard curriculum expectations and can supplement any math program. Generate multiple worksheets to create a full practice set.