Data Management (MDM4U) · Probability Distributions

Z-Scores and the Standard Normal Distribution

10 tutor-authored questions for this Ontario curriculum expectation, ordered easiest to hardest — every one with a full worked solution. Work through them free, no account needed.

Start the 10 questions Curriculum: MDM4U-PD.5

Sample: the first question, solved

What is a "z-score"?

📘 Worked solution
A measure of how many standard deviations a value is from the mean.

And one from the hard end

A distribution has μ=50, σ=10. Find the z-score for x=65.

Solution shown after you try it in practice mode.

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