correlationA pattern where two quantities tend to change together: both rise, or one falls as the other rises. It does not prove that one causes the other.
You’ll leave with these skills
01Predict how one extreme value changes the mean and the medianLook for one value far from the rest, and expect it to pull the mean toward it while the median barely moves.
02Find a missing value or a combined mean from totalsMultiply each mean by how many values it covers to get a total, then add or subtract totals and divide by the new count.
03Find the mean and the median from a frequency tableFor the mean, add value times frequency and divide by the total frequency. For the median, use cumulative frequencies to locate the middle observation, or the two middle observations if the count is even.
04Find the mean or the median of a long list in DesmosType the list of values inside Desmos’s mean or median command to get the answer without adding or sorting by hand.
This lesson is part of the full library
207 lessons that teach every skill the SAT tests
71Math
40Reading
24Grammar
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