Before You Begin

This mock exam contains 15 hand-picked, high-difficulty problems covering the exact traps and calculation patterns that trip up top students most often: modular arithmetic, casework counting, conditional probability, ratio/algebra systems, and geometric area reasoning.

• Tap any answer choice to lock it in — the full step-by-step explanation appears immediately below the question.
• Use the floating Desmos calculator (bottom-right) for any arithmetic checks.
• Click Print / PDF for an ink-friendly black-and-white copy with an answer key on the last page.
• Work every problem twice: once under time pressure, once slowly re-deriving the logic in the explanation.