SAT Math · 6 min read · Published February 12, 2026

    SAT Percentages: The Fast Way

    Percent change, percent of, and reverse-percent questions on the Digital SAT — all solved with one consistent formula.

    The One Formula You Need

    Percent = (part / whole) × 100. Every SAT percent question can be rewritten to fit this, then rearranged algebraically.

    Percent Change

    Percent change = ((new − old) / old) × 100. Always divide by the original number, not the final one — mixing these up is the most common SAT percent mistake.

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