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Harvard-MIT Mathematics Tournament #0izb

Harvard-MIT Mathematics TournamentHard

From module Angle Chasing Mastery

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Understand the scale
Scale 0.5: Easiest math competition problems, often solvable even for early middle school students without experience. 1: Problems strictly for beginners, often at a moderate middle school level. 1.5: Problems for stronger beginner students, on the level of the middling problems in most middle school contests. 2: For motivated beginners, harder questions from the previous categories. 2.5: More advanced beginner problems, hardest questions from previous categories. 3: Early intermediate problems that require more creative thinking. 3.5: Tougher early intermediate problems that consistently stretch into higher-level creative thinking or conceptual knowledge. 4: Intermediate-level problems. 4.5: Upper intermediate problems approaching the upper bound for non-invitational sprint math competitions. 5: More difficult AIME problems or simple proof-based Olympiad-style problems. 6: High-level AIME-styled questions or introductory Olympiad-level questions. 7: Tougher Olympiad-level questions, may require more technical knowledge. 8: High-level Olympiad-level questions. 9: Expert Olympiad-level questions. 9.5: The hardest problems appearing on Olympiads which the strongest students could reasonably solve. 10: Historically notorious problems, generally unsuitable for even very hard competitions because they are exceedingly tedious, long, and difficult.
TangentsRadical axis theoremSpiral similarityAngle chasingTriangle trigonometry

Problem

Problem:

Circles ω1\omega_{1} and ω2\omega_{2} intersect at points AA and BB. Segment PQPQ is tangent to ω1\omega_{1} at PP and to ω2\omega_{2} at QQ, and AA is closer to PQPQ than BB. Point XX is on ω1\omega_{1} such that PX∥QBPX \parallel QB, and point YY is on ω2\omega_{2} such that QY∥PBQY \parallel PB. Given that ∠APQ=30∘\angle APQ = 30^{\circ} and ∠PQA=15∘\angle PQA = 15^{\circ}, find the ratio AX/AYAX / AY.

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