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

Showing 385–432 of 1,198

  • 3.17Geometry

    Locked

    Inscribed circle

    Difficulty 3 of 9+45 XP

  • 3.18Combinatorics

    Locked

    Letters in wrong envelopes

    Difficulty 3 of 9+45 XP

  • 3.19Functions

    Locked

    Function from f(2x)

    Difficulty 3 of 9+45 XP

  • 3.20Calculus

    Locked

    Local maximum

    Difficulty 3 of 9+45 XP

  • 3.21Logic

    Locked

    One hundred lockers

    Difficulty 3 of 9+45 XP

  • 3.22Equations

    Locked

    Logarithmic equation II

    Difficulty 3 of 9+45 XP

  • 3.23Calculus

    Locked

    Integral of sine

    Difficulty 3 of 9+45 XP

  • 3.24Combinatorics

    Locked

    Increasing digits

    Difficulty 3 of 9+45 XP

  • 3.25Algebra

    Locked

    Symmetric expressions

    Difficulty 3 of 9+45 XP

  • 3.26Probability

    Locked

    Three dice, sum 10

    Difficulty 3 of 9+45 XP

  • 3.27Geometry

    Locked

    Largest rectangle in a circle

    Difficulty 3 of 9+45 XP

  • 3.28Arithmetic

    Locked

    Last two digits

    Difficulty 3 of 9+45 XP

  • 3.29Functions

    Locked

    Functional equation

    Difficulty 3 of 9+45 XP

  • 3.30Calculus

    Locked

    Integration by parts

    Difficulty 3 of 9+45 XP

  • 3.31Algebra

    Locked

    Powers with fractional exponents

    Difficulty 3 of 9+45 XP

  • 3.32Functions

    Locked

    Where the line meets the x-axis

    Difficulty 3 of 9+45 XP

  • 3.33Geometry

    Locked

    The width of a lake

    Difficulty 3 of 9+45 XP

  • 3.34Arithmetic

    Locked

    A huge power of two and seven

    Difficulty 3 of 9+45 XP

  • 3.35Equations

    Locked

    Two linear inequalities at once

    Difficulty 3 of 9+45 XP

  • 3.36Functions

    Locked

    Two proportions through one point

    Difficulty 3 of 9+45 XP

  • 3.37Geometry

    Locked

    Bisectors of two angles of a quadrilateral

    Difficulty 3 of 9+45 XP

  • 3.38Logic

    Locked

    A union without the intersection

    Difficulty 3 of 9+45 XP

  • 3.39Algebra

    Locked

    Roots in the denominator

    Difficulty 3 of 9+45 XP

  • 3.40Functions

    Locked

    The sum of the vertex coordinates

    Difficulty 3 of 9+45 XP

  • 3.41Geometry

    Locked

    The foot of the altitude on the hypotenuse

    Difficulty 3 of 9+45 XP

  • 3.42Combinatorics

    Locked

    Four-digit numbers ending in five or zero

    Difficulty 3 of 9+45 XP

  • 3.43Equations

    Locked

    The larger of two roots

    Difficulty 3 of 9+45 XP

  • 3.44Functions

    Locked

    Composition both ways round

    Difficulty 3 of 9+45 XP

  • 3.45Geometry

    Locked

    How steep is the cable car

    Difficulty 3 of 9+45 XP

  • 3.46Logic

    Locked

    Rows of a truth table

    Difficulty 3 of 9+45 XP

  • 3.47Algebra

    Locked

    A quotient of two algebraic fractions

    Difficulty 3 of 9+45 XP

  • 3.48Functions

    Locked

    A function in three pieces

    Difficulty 3 of 9+45 XP

  • 3.49Geometry

    Locked

    Two tangents from one point

    Difficulty 3 of 9+45 XP

  • 3.50Arithmetic

    Locked

    The sum of two repeating decimals

    Difficulty 3 of 9+45 XP

  • 3.51Equations

    Locked

    An absolute value on one side

    Difficulty 3 of 9+45 XP

  • 3.52Functions

    Locked

    A shifted graph

    Difficulty 3 of 9+45 XP

  • 3.53Geometry

    Locked

    A trapezoid cut along its midline

    Difficulty 3 of 9+45 XP

  • 3.54Combinatorics

    Locked

    A committee with posts

    Difficulty 3 of 9+45 XP

  • 3.55Algebra

    Locked

    Huge powers of two

    Difficulty 3 of 9+45 XP

  • 3.56Functions

    Locked

    Where two lines cross

    Difficulty 3 of 9+45 XP

  • 3.57Geometry

    Locked

    From the circumcircle to the incircle

    Difficulty 3 of 9+45 XP

  • 3.58Arithmetic

    Locked

    Divisors that six divides

    Difficulty 3 of 9+45 XP

  • 3.59Equations

    Locked

    A fourth-degree equation by substitution

    Difficulty 3 of 9+45 XP

  • 3.60Functions

    Locked

    A triangle at the axes

    Difficulty 3 of 9+45 XP

  • 3.61Geometry

    Locked

    A cut parallel to a side

    Difficulty 3 of 9+45 XP

  • 3.62Logic

    Locked

    Three foreign languages in a class

    Difficulty 3 of 9+45 XP

  • 3.63Algebra

    Locked

    Substituting a big number

    Difficulty 3 of 9+45 XP

  • 3.64Functions

    Locked

    Integers in the domain

    Difficulty 3 of 9+45 XP