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

Showing 577–624 of 1,198

  • 4.79Equations

    Locked

    Nines and threes

    Difficulty 4 of 9+80 XP

  • 4.80Functions

    Locked

    Comparing logarithms

    Difficulty 4 of 9+80 XP

  • 4.81Geometry

    Locked

    The length of a vector combination

    Difficulty 4 of 9+80 XP

  • 4.82Combinatorics

    Locked

    A difference of two binomial coefficients

    Difficulty 4 of 9+80 XP

  • 4.83Equations

    Locked

    Two base-3 logarithms

    Difficulty 4 of 9+80 XP

  • 4.84Calculus

    Locked

    Squares inscribed forever

    Difficulty 4 of 9+80 XP

  • 4.85Geometry

    Locked

    A square between parallel lines

    Difficulty 4 of 9+80 XP

  • 4.86Probability

    Locked

    The variance of six measurements

    Difficulty 4 of 9+80 XP

  • 4.87Equations

    Locked

    Sine squared

    Difficulty 4 of 9+80 XP

  • 4.88Functions

    Locked

    Simplifying with shifted angles

    Difficulty 4 of 9+80 XP

  • 4.89Geometry

    Locked

    A triangle under two lines

    Difficulty 4 of 9+80 XP

  • 4.90Combinatorics

    Locked

    A betting slip

    Difficulty 4 of 9+80 XP

  • 4.91Equations

    Locked

    A base smaller than one

    Difficulty 4 of 9+80 XP

  • 4.92Calculus

    Locked

    A growing town

    Difficulty 4 of 9+80 XP

  • 4.93Geometry

    Locked

    A ship changes course

    Difficulty 4 of 9+80 XP

  • 4.94Probability

    Locked

    Who takes the bus

    Difficulty 4 of 9+80 XP

  • 4.95Equations

    Locked

    When do we pass €7,000

    Difficulty 4 of 9+80 XP

  • 4.96Functions

    Locked

    An angle in the third quadrant

    Difficulty 4 of 9+80 XP

  • 4.97Geometry

    Locked

    A triangle with an obtuse angle

    Difficulty 4 of 9+80 XP

  • 4.98Combinatorics

    Locked

    Scoops in a cup

    Difficulty 4 of 9+80 XP

  • 4.99Geometry

    Locked

    Pellets from a metal cylinder

    Difficulty 4 of 9+80 XP

  • 4.100Probability

    Locked

    The first black one on the third try

    Difficulty 4 of 9+80 XP

  • 4.101Equations

    Locked

    A difference of absolute values

    Difficulty 4 of 9+80 XP

  • 4.102Functions

    Locked

    An exponential and four lines

    Difficulty 4 of 9+80 XP

  • 4.103Geometry

    Locked

    A tangent and the x-axis

    Difficulty 4 of 9+80 XP

  • 4.104Combinatorics

    Locked

    The middle term of an expansion

    Difficulty 4 of 9+80 XP

  • 4.105Equations

    Locked

    Signs in a quotient

    Difficulty 4 of 9+80 XP

  • 4.106Calculus

    Locked

    A pile of pipes

    Difficulty 4 of 9+80 XP

  • 4.107Geometry

    Locked

    A pyramid surface from the slope of its faces

    Difficulty 4 of 9+80 XP

  • 4.108Probability

    Locked

    An alarm with three sensors

    Difficulty 4 of 9+80 XP

  • 4.109Equations

    Locked

    A logarithmic inequality with conditions

    Difficulty 4 of 9+80 XP

  • 4.110Functions

    Locked

    The period of a sum

    Difficulty 4 of 9+80 XP

  • 4.111Geometry

    Locked

    A circle through three points

    Difficulty 4 of 9+80 XP

  • 4.112Combinatorics

    Locked

    More girls than boys

    Difficulty 4 of 9+80 XP

  • 4.113Equations

    Locked

    The logarithm of a square

    Difficulty 4 of 9+80 XP

  • 4.114Calculus

    Locked

    A bouncing ball

    Difficulty 4 of 9+80 XP

  • 4.115Geometry

    Locked

    The diagonals of a parallelogram

    Difficulty 4 of 9+80 XP

  • 4.116Probability

    Locked

    Is the game worth playing?

    Difficulty 4 of 9+80 XP

  • 4.117Equations

    Locked

    A product equal to zero

    Difficulty 4 of 9+80 XP

  • 4.118Functions

    Locked

    The inverse function twice in a row

    Difficulty 4 of 9+80 XP

  • 4.119Geometry

    Locked

    A corner cut off a cube

    Difficulty 4 of 9+80 XP

  • 4.120Combinatorics

    Locked

    An ice-hockey game 4 : 3

    Difficulty 4 of 9+80 XP

  • 4.121Equations

    Locked

    A line through a circle

    Difficulty 4 of 9+80 XP

  • 4.122Calculus

    Locked

    The difference of the two before

    Difficulty 4 of 9+80 XP

  • 4.123Geometry

    Locked

    The width of a river

    Difficulty 4 of 9+80 XP

  • 4.124Probability

    Locked

    The largest number on three dice

    Difficulty 4 of 9+80 XP

  • 4.125Equations

    Locked

    A decaying isotope

    Difficulty 4 of 9+80 XP

  • 4.126Functions

    Locked

    The even and the odd part

    Difficulty 4 of 9+80 XP