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

Showing 193–240 of 1,198

  • 1.193Arithmetic

    Locked

    A half and a third

    Difficulty 1 of 9+5 XP

  • 1.194Fractions

    Locked

    The smallest denominator

    Difficulty 1 of 9+5 XP

  • 1.195Algebra

    Locked

    A sequence that keeps subtracting

    Difficulty 1 of 9+5 XP

  • 1.196Geometry

    Locked

    A square and two equilateral triangles

    Difficulty 1 of 9+5 XP

  • 2.1Arithmetic

    Locked

    Percentages

    Difficulty 2 of 9+20 XP

  • 2.2Fractions

    Locked

    Multiplying fractions

    Difficulty 2 of 9+20 XP

  • 2.3Equations

    Locked

    Linear equation

    Difficulty 2 of 9+20 XP

  • 2.4Geometry

    Locked

    Triangle area

    Difficulty 2 of 9+20 XP

  • 2.5Logic

    Locked

    Clock in 100 hours

    Difficulty 2 of 9+20 XP

  • 2.6Algebra

    Locked

    Sum of squares

    Difficulty 2 of 9+20 XP

  • 2.7Functions

    Locked

    Function value

    Difficulty 2 of 9+20 XP

  • 2.8Probability

    Locked

    Marbles in a bag

    Difficulty 2 of 9+20 XP

  • 2.9Combinatorics

    Locked

    Books on a shelf

    Difficulty 2 of 9+20 XP

  • 2.10Arithmetic

    Locked

    Powers

    Difficulty 2 of 9+20 XP

  • 2.11Fractions

    Locked

    Dividing fractions

    Difficulty 2 of 9+20 XP

  • 2.12Equations

    Locked

    Equation with brackets

    Difficulty 2 of 9+20 XP

  • 2.13Geometry

    Locked

    Rectangle from perimeter

    Difficulty 2 of 9+20 XP

  • 2.14Logic

    Locked

    Peter and Jana’s ages

    Difficulty 2 of 9+20 XP

  • 2.15Arithmetic

    Locked

    Arithmetic mean

    Difficulty 2 of 9+20 XP

  • 2.16Functions

    Locked

    Quadratic function

    Difficulty 2 of 9+20 XP

  • 2.17Probability

    Locked

    Die roll

    Difficulty 2 of 9+20 XP

  • 2.18Combinatorics

    Locked

    Two-letter codes

    Difficulty 2 of 9+20 XP

  • 2.19Algebra

    Locked

    Difference of squares

    Difficulty 2 of 9+20 XP

  • 2.20Equations

    Locked

    Equation with a fraction

    Difficulty 2 of 9+20 XP

  • 2.21Algebra

    Locked

    Square equation

    Difficulty 2 of 9+20 XP

  • 2.22Geometry

    Locked

    Rhombus area

    Difficulty 2 of 9+20 XP

  • 2.23Probability

    Locked

    Sum of 12 on dice

    Difficulty 2 of 9+20 XP

  • 2.24Combinatorics

    Locked

    Handshakes of seven people

    Difficulty 2 of 9+20 XP

  • 2.25Arithmetic

    Locked

    Square of 17

    Difficulty 2 of 9+20 XP

  • 2.26Fractions

    Locked

    Compound fraction expression

    Difficulty 2 of 9+20 XP

  • 2.27Equations

    Locked

    System of equations

    Difficulty 2 of 9+20 XP

  • 2.28Functions

    Locked

    Equation with a function

    Difficulty 2 of 9+20 XP

  • 2.29Logic

    Locked

    A brick and half a brick

    Difficulty 2 of 9+20 XP

  • 2.30Geometry

    Locked

    Cuboid volume

    Difficulty 2 of 9+20 XP

  • 2.31Arithmetic

    Locked

    Digit sum of a power

    Difficulty 2 of 9+20 XP

  • 2.32Algebra

    Locked

    Equation with distribution

    Difficulty 2 of 9+20 XP

  • 2.33Probability

    Locked

    King from a deck

    Difficulty 2 of 9+20 XP

  • 2.34Combinatorics

    Locked

    Words starting with A

    Difficulty 2 of 9+20 XP

  • 2.35Equations

    Locked

    Equation by factoring

    Difficulty 2 of 9+20 XP

  • 2.36Functions

    Locked

    Line through two points

    Difficulty 2 of 9+20 XP

  • 2.37Geometry

    Locked

    Isosceles right triangle

    Difficulty 2 of 9+20 XP

  • 2.38Fractions

    Locked

    Dividing in a ratio

    Difficulty 2 of 9+20 XP

  • 2.39Logic

    Locked

    Three even numbers

    Difficulty 2 of 9+20 XP

  • 2.40Arithmetic

    Locked

    Clever multiplication

    Difficulty 2 of 9+20 XP

  • 2.41Geometry

    Locked

    Area of a circle

    Difficulty 2 of 9+20 XP

  • 2.42Geometry

    Locked

    Edge of a cube

    Difficulty 2 of 9+20 XP

  • 2.43Algebra

    Locked

    Expression with a reciprocal

    Difficulty 2 of 9+20 XP

  • 2.44Equations

    Locked

    Quadratic equation II

    Difficulty 2 of 9+20 XP