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  • 1,198 problems
  • 9 difficulty levels
  • +5 to +405 XP per problem
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All problems

Showing 721–768 of 1,198

  • 5.73Geometry

    Locked

    A lighthouse seen from two places

    Difficulty 5 of 9+125 XP

  • 5.74Probability

    Locked

    Median and mean of marks

    Difficulty 5 of 9+125 XP

  • 5.75Equations

    Locked

    Two absolute values

    Difficulty 5 of 9+125 XP

  • 5.76Algebra

    Locked

    A sum of two fractions with roots

    Difficulty 5 of 9+125 XP

  • 5.77Functions

    Locked

    A parabola through three points

    Difficulty 5 of 9+125 XP

  • 5.78Geometry

    Locked

    The angle of two lines given differently

    Difficulty 5 of 9+125 XP

  • 5.79Combinatorics

    Locked

    A school committee

    Difficulty 5 of 9+125 XP

  • 5.80Equations

    Locked

    A squared logarithm

    Difficulty 5 of 9+125 XP

  • 5.81Calculus

    Locked

    The derivative of a quotient at a point

    Difficulty 5 of 9+125 XP

  • 5.82Geometry

    Locked

    Mirroring a point in a line

    Difficulty 5 of 9+125 XP

  • 5.83Probability

    Locked

    The spread of competition scores

    Difficulty 5 of 9+125 XP

  • 5.84Algebra

    Locked

    An equation with a given complex root

    Difficulty 5 of 9+125 XP

  • 5.85Functions

    Locked

    Where two exponentials meet

    Difficulty 5 of 9+125 XP

  • 5.86Geometry

    Locked

    Two ships leave the harbour

    Difficulty 5 of 9+125 XP

  • 5.87Combinatorics

    Locked

    Siblings at the cinema

    Difficulty 5 of 9+125 XP

  • 5.88Equations

    Locked

    When both roots coincide

    Difficulty 5 of 9+125 XP

  • 5.89Calculus

    Locked

    A difference of two roots

    Difficulty 5 of 9+125 XP

  • 5.90Geometry

    Locked

    The chord cut off by a line

    Difficulty 5 of 9+125 XP

  • 5.91Combinatorics

    Locked

    A coefficient in a product

    Difficulty 5 of 9+125 XP

  • 5.92Algebra

    Locked

    Two solutions and water

    Difficulty 5 of 9+125 XP

  • 5.93Functions

    Locked

    Cosine over two turns

    Difficulty 5 of 9+125 XP

  • 5.94Arithmetic

    Locked

    Wages rise, prices rise faster

    Difficulty 5 of 9+125 XP

  • 5.95Probability

    Locked

    Guessing in a test

    Difficulty 5 of 9+125 XP

  • 5.96Equations

    Locked

    A logarithmic inequality and its domain

    Difficulty 5 of 9+125 XP

  • 5.97Calculus

    Locked

    Where the tangent crosses the x-axis

    Difficulty 5 of 9+125 XP

  • 5.98Arithmetic

    Locked

    Divisors that are squares

    Difficulty 5 of 9+125 XP

  • 5.99Probability

    Locked

    A random parameter of an equation

    Difficulty 5 of 9+125 XP

  • 5.100Algebra

    Locked

    One of the pair left

    Difficulty 5 of 9+125 XP

  • 5.101Functions

    Locked

    A quadratic of an exponential

    Difficulty 5 of 9+125 XP

  • 5.102Geometry

    Locked

    A tangent cuts off a triangle

    Difficulty 5 of 9+125 XP

  • 5.103Combinatorics

    Locked

    Five-digit numbers divisible by three

    Difficulty 5 of 9+125 XP

  • 5.104Algebra

    Locked

    A polynomial with two unknown coefficients

    Difficulty 5 of 9+125 XP

  • 5.105Calculus

    Locked

    Extremes of a cubic on an interval

    Difficulty 5 of 9+125 XP

  • 5.106Geometry

    Locked

    A pyramid known from its surface area

    Difficulty 5 of 9+125 XP

  • 5.107Logic

    Locked

    Divides if and only if…

    Difficulty 5 of 9+125 XP

  • 5.108Equations

    Locked

    A difference of two square roots

    Difficulty 5 of 9+125 XP

  • 5.109Functions

    Locked

    The range of a trigonometric function

    Difficulty 5 of 9+125 XP

  • 5.110Arithmetic

    Locked

    The sum of selected three-digit numbers

    Difficulty 5 of 9+125 XP

  • 5.111Fractions

    Locked

    An equation with a continued fraction

    Difficulty 5 of 9+125 XP

  • 5.112Algebra

    Locked

    A new equation from the roots of an old one

    Difficulty 5 of 9+125 XP

  • 5.113Calculus

    Locked

    A rectangle under a parabola

    Difficulty 5 of 9+125 XP

  • 5.114Geometry

    Locked

    A circle around a triangular plot

    Difficulty 5 of 9+125 XP

  • 5.115Combinatorics

    Locked

    From one coefficient to another

    Difficulty 5 of 9+125 XP

  • 5.116Equations

    Locked

    A sum of squares and a product

    Difficulty 5 of 9+125 XP

  • 5.117Functions

    Locked

    The period of a sum of three functions

    Difficulty 5 of 9+125 XP

  • 5.118Geometry

    Locked

    The length of a combination of vectors

    Difficulty 5 of 9+125 XP

  • 5.119Probability

    Locked

    Two sixes and one one

    Difficulty 5 of 9+125 XP

  • 5.120Equations

    Locked

    Fours and threes with half exponents

    Difficulty 5 of 9+125 XP