1600SAT Logo All SAT Skills
    Problem Solving & Data AnalysisMedium

    Two-variable data: Models and scatterplots

    Interpret scatterplots, identify correlation, and use lines of best fit to make predictions.

    Sample SAT Problem

    A line of best fit is y = 2.5x + 10. Predict y when x = 8.

    Show SolutionHide Solution

    Step-by-Step Solution

    y = 2.5(8) + 10 = 20 + 10 = 30.

    Key Tips from Pamela

    • Positive slope = positive correlation; negative slope = negative correlation.
    • The line of best fit minimizes the total distance from all data points.
    • Only predict within or near the data range — extrapolation can be unreliable.

    Still stuck on two-variable data: models and scatterplots?

    Send me your exact problem. I'll write out the solution by hand and email it to you — completely free.

    Send Me Your Problem