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

Showing 769–816 of 1,198

  • 5.121Calculus

    Locked

    A region between a parabola and a line

    Difficulty 5 of 9+125 XP

  • 5.122Geometry

    Locked

    A triangle in a hexagon

    Difficulty 5 of 9+125 XP

  • 5.123Combinatorics

    Locked

    Triangles in a grid

    Difficulty 5 of 9+125 XP

  • 5.124Arithmetic

    Locked

    When the smaller deposit catches up

    Difficulty 5 of 9+125 XP

  • 5.125Probability

    Locked

    Which urn?

    Difficulty 5 of 9+125 XP

  • 5.126Algebra

    Locked

    Two trips of a motorboat

    Difficulty 5 of 9+125 XP

  • 5.127Functions

    Locked

    From the sum of sine and cosine

    Difficulty 5 of 9+125 XP

  • 5.128Geometry

    Locked

    A cone in a ball

    Difficulty 5 of 9+125 XP

  • 5.129Logic

    Locked

    Three sets with no common element

    Difficulty 5 of 9+125 XP

  • 5.130Equations

    Locked

    The unknown in the base and in the exponent

    Difficulty 5 of 9+125 XP

  • 5.131Calculus

    Locked

    A sequence from two conditions

    Difficulty 5 of 9+125 XP

  • 5.132Geometry

    Locked

    The slope of a lateral edge

    Difficulty 5 of 9+125 XP

  • 5.133Probability

    Locked

    Closer to a corner than to the centre

    Difficulty 5 of 9+125 XP

  • 5.134Algebra

    Locked

    A sum of two cube roots

    Difficulty 5 of 9+125 XP

  • 5.135Functions

    Locked

    The sum of solutions over five periods

    Difficulty 5 of 9+125 XP

  • 5.136Geometry

    Locked

    A cylinder with a square axial section in a cone

    Difficulty 5 of 9+125 XP

  • 5.137Combinatorics

    Locked

    Three teams of four

    Difficulty 5 of 9+125 XP

  • 5.138Algebra

    Locked

    A complex number and its modulus

    Difficulty 5 of 9+125 XP

  • 5.139Calculus

    Locked

    A tangent and the y-axis

    Difficulty 5 of 9+125 XP

  • 5.140Arithmetic

    Locked

    Regular saving

    Difficulty 5 of 9+125 XP

  • 5.141Probability

    Locked

    A raffle

    Difficulty 5 of 9+125 XP

  • 5.142Equations

    Locked

    Roots of opposite signs

    Difficulty 5 of 9+125 XP

  • 5.143Functions

    Locked

    A function and its inverse

    Difficulty 5 of 9+125 XP

  • 5.144Geometry

    Locked

    Circles touching two lines

    Difficulty 5 of 9+125 XP

  • 5.145Combinatorics

    Locked

    Rational terms of an expansion

    Difficulty 5 of 9+125 XP

  • 5.146Equations

    Locked

    Squares and cubes in a system

    Difficulty 5 of 9+125 XP

  • 5.147Calculus

    Locked

    A parabola with a given area

    Difficulty 5 of 9+125 XP

  • 5.148Arithmetic

    Locked

    A three-year loan

    Difficulty 5 of 9+125 XP

  • 5.149Probability

    Locked

    Given that a six came up

    Difficulty 5 of 9+125 XP

  • 5.150Calculus

    Locked

    Growing instalments

    Difficulty 5 of 9+125 XP

  • 6.1Equations

    Locked

    An exponential equation with base 2

    Difficulty 6 of 9+180 XP

  • 6.2Functions

    Locked

    A parabola from its vertex and a point

    Difficulty 6 of 9+180 XP

  • 6.3Geometry

    Locked

    An altitude from coordinates

    Difficulty 6 of 9+180 XP

  • 6.4Probability

    Locked

    A class average and a newcomer

    Difficulty 6 of 9+180 XP

  • 6.5Algebra

    Locked

    Ratios of the roots of a quadratic

    Difficulty 6 of 9+180 XP

  • 6.6Calculus

    Locked

    A 0/0 limit with a square root

    Difficulty 6 of 9+180 XP

  • 6.7Arithmetic

    Locked

    Divisors with a condition

    Difficulty 6 of 9+180 XP

  • 6.8Combinatorics

    Locked

    An equation with binomial coefficients

    Difficulty 6 of 9+180 XP

  • 6.9Algebra

    Locked

    An expression with logarithms and a power

    Difficulty 6 of 9+180 XP

  • 6.10Functions

    Locked

    A double angle in the second quadrant

    Difficulty 6 of 9+180 XP

  • 6.11Geometry

    Locked

    The altitude opposite an obtuse angle

    Difficulty 6 of 9+180 XP

  • 6.12Fractions

    Locked

    Arithmetic with repeating decimals

    Difficulty 6 of 9+180 XP

  • 6.13Algebra

    Locked

    Two pipes and a pool

    Difficulty 6 of 9+180 XP

  • 6.14Calculus

    Locked

    A series and the series of its squares

    Difficulty 6 of 9+180 XP

  • 6.15Arithmetic

    Locked

    Back to the original price

    Difficulty 6 of 9+180 XP

  • 6.16Logic

    Locked

    Three clubs

    Difficulty 6 of 9+180 XP

  • 6.17Equations

    Locked

    A quartic equation by substitution

    Difficulty 6 of 9+180 XP

  • 6.18Functions

    Locked

    The inverse of a composite function

    Difficulty 6 of 9+180 XP