Confidence Intervals
30 tutor-authored questions for this Ontario curriculum expectation, ordered easiest to hardest, every one with a full worked solution. Work through all 30 with your weekly-lesson access code.
Sample: the first question, solved
What is a "confidence interval"?
📘 Worked solution
✓A range of values likely to contain the true population parameter, with a stated confidence level.
And one from the hard end
"A university survey (n=60) finds a 95% CI of (3.4, 4.2) for average study hours per day. A follow-up survey at a different school (n=600) finds a 95% CI of (3.6, 4.0) with a similar point estimate. Explain why the second interval is narrower, and state what would happen to its width if the confidence level were raised to 99%."
Solution shown after you try it in practice mode.
Work through all 30, easiest to hardest
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