Curriculum placement
Precalculus. This describes the skill, not a learner estimate.
Defining a random variable
Define a numerical random variable and graph its probability distribution
Problem types
- Random variables and their distributions
Builds on
- Probability of compound events
- Dot plots, histograms, and box plots
- Unions, intersections, and complements · Earlier idea
A random variable assigns a number to each outcome, so its values are described by event sets of outcomes.
- The addition rule for probability · Useful idea
The probabilities of all values of a random variable add to 1 because the events are disjoint and cover the sample space.
Leads to
- A distribution built from frequencies
- A distribution from a sample space
- The normal distribution · Extend the idea
A continuous random variable with a bell-shaped distribution is described by a mean and standard deviation.
Related skills
- A margin of error from simulated samples · Related idea
A sample mean varies from sample to sample, so it is a random variable with its own distribution.
- Finding a conditional probability · Shared foundations
- Permutations and combinations · Shared foundations
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