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Number Theory

Number Theory

  • Divisibility Shortcuts
  • Exploring Infinity
  • Factor Trees
  • Fermat's Little Theorem
  • Greatest Common Divisor
  • Least Common Multiple
  • Modular Arithmetic
  • Modular Congruence
  • Modular Inverses
  • Prime Factorization
  • The 100 Doors Puzzle
  • Totients


  • Binary
  • Truth Tables
  • Logic Gates
  • Venn and Euler Diagrams
  • Propositional Logic
  • The Square of Opposition
  • De Morgan's Laws
  • Inclusive and Exclusive OR
  • Combinatorics
  • Knight and Knave Puzzles
  • Combinatorial Game Algorithms
Contest Math

Contest Math

  • Angle Hunting
  • Composite Figures
  • Counting Strategies
  • Factorials
  • Mean, Median, Mode
  • Probability
  • Problem Solving
  • Prime Factorization
  • Sequences and Series
  • Similarity
  • Venn Diagrams
Introduction to Probability

Introduction to Probability

  • Estimating Probability
  • Rule of Sum
  • Rule of Product
  • Conditional Probability
  • Bayes' Rule
  • Dependence and Independence
  • Cumulative Probabilities
  • Probability Estimates
  • Updating Probabilities
  • Probability Simulation

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Courses in Foundational Math

  • Solving Equations
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  • Geometry I
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