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

Showing 433–480 of 1,198

  • 3.65Geometry

    Locked

    The other leg from a segment of the hypotenuse

    Difficulty 3 of 9+45 XP

  • 3.66Combinatorics

    Locked

    The girls do not sit together

    Difficulty 3 of 9+45 XP

  • 3.67Equations

    Locked

    A quadratic inequality with a condition

    Difficulty 3 of 9+45 XP

  • 3.68Functions

    Locked

    A triangle from the intercepts of a parabola

    Difficulty 3 of 9+45 XP

  • 3.69Geometry

    Locked

    A tangent, a chord and an inscribed triangle

    Difficulty 3 of 9+45 XP

  • 3.70Arithmetic

    Locked

    Two missing digits

    Difficulty 3 of 9+45 XP

  • 3.71Algebra

    Locked

    A number and its reciprocal

    Difficulty 3 of 9+45 XP

  • 3.72Functions

    Locked

    The spread of values on an interval

    Difficulty 3 of 9+45 XP

  • 3.73Geometry

    Locked

    Two chords on the same side

    Difficulty 3 of 9+45 XP

  • 3.74Logic

    Locked

    Counterexamples to a general statement

    Difficulty 3 of 9+45 XP

  • 3.75Algebra

    Locked

    A long sum of fractions with roots

    Difficulty 3 of 9+45 XP

  • 3.76Functions

    Locked

    A taxi price list

    Difficulty 3 of 9+45 XP

  • 3.77Geometry

    Locked

    The height of a rhombus

    Difficulty 3 of 9+45 XP

  • 3.78Combinatorics

    Locked

    The same initials

    Difficulty 3 of 9+45 XP

  • 3.79Equations

    Locked

    The diagonal of a plot

    Difficulty 3 of 9+45 XP

  • 3.80Functions

    Locked

    A garden by a wall, with a gate

    Difficulty 3 of 9+45 XP

  • 3.81Geometry

    Locked

    A quadrilateral inscribed in a circle

    Difficulty 3 of 9+45 XP

  • 3.82Arithmetic

    Locked

    An unknown base

    Difficulty 3 of 9+45 XP

  • 3.83Algebra

    Locked

    Roots written as powers

    Difficulty 3 of 9+45 XP

  • 3.84Functions

    Locked

    Raising the price of T-shirts

    Difficulty 3 of 9+45 XP

  • 3.85Geometry

    Locked

    The point of contact on the hypotenuse

    Difficulty 3 of 9+45 XP

  • 3.86Logic

    Locked

    Tea, coffee and cocoa

    Difficulty 3 of 9+45 XP

  • 3.87Equations

    Locked

    Three equations, three unknowns

    Difficulty 3 of 9+45 XP

  • 3.88Functions

    Locked

    The least value and what lies above it

    Difficulty 3 of 9+45 XP

  • 3.89Geometry

    Locked

    A segment above a side of a triangle

    Difficulty 3 of 9+45 XP

  • 3.90Combinatorics

    Locked

    Four-digit multiples of four

    Difficulty 3 of 9+45 XP

  • 3.91Algebra

    Locked

    A root inside a root

    Difficulty 3 of 9+45 XP

  • 3.92Functions

    Locked

    A hyperbola, a line and the origin

    Difficulty 3 of 9+45 XP

  • 3.93Geometry

    Locked

    A regular octagon

    Difficulty 3 of 9+45 XP

  • 3.94Arithmetic

    Locked

    Pairs with a given GCD and LCM

    Difficulty 3 of 9+45 XP

  • 3.95Equations

    Locked

    A sum of two distances

    Difficulty 3 of 9+45 XP

  • 3.96Functions

    Locked

    Reflect, then shift

    Difficulty 3 of 9+45 XP

  • 3.97Geometry

    Locked

    How long is the angle bisector

    Difficulty 3 of 9+45 XP

  • 3.98Logic

    Locked

    Sixteen rows of a table

    Difficulty 3 of 9+45 XP

  • 3.99Equations

    Locked

    A faster train

    Difficulty 3 of 9+45 XP

  • 3.100Functions

    Locked

    When the order does not matter

    Difficulty 3 of 9+45 XP

  • 3.101Geometry

    Locked

    The longer diagonal of a trapezoid

    Difficulty 3 of 9+45 XP

  • 3.102Combinatorics

    Locked

    The letters of KOLOTOČ

    Difficulty 3 of 9+45 XP

  • 3.103Equations

    Locked

    A repeated expression in an equation

    Difficulty 3 of 9+45 XP

  • 3.104Functions

    Locked

    A linear function composed with itself

    Difficulty 3 of 9+45 XP

  • 3.105Geometry

    Locked

    A tower and two angles of elevation

    Difficulty 3 of 9+45 XP

  • 3.106Arithmetic

    Locked

    The last digit of a sum of powers

    Difficulty 3 of 9+45 XP

  • 3.107Equations

    Locked

    A new equation from old roots

    Difficulty 3 of 9+45 XP

  • 3.108Functions

    Locked

    A ball’s height from three readings

    Difficulty 3 of 9+45 XP

  • 3.109Geometry

    Locked

    A chord split by a point

    Difficulty 3 of 9+45 XP

  • 3.110Logic

    Locked

    Three contest problems

    Difficulty 3 of 9+45 XP

  • 3.111Algebra

    Locked

    Three numbers adding up to zero

    Difficulty 3 of 9+45 XP

  • 3.112Functions

    Locked

    A hundred times in a row

    Difficulty 3 of 9+45 XP