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

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Showing 337–384 of 1,198

2.141Algebra
Locked
Rational expressions and the year 2026
Difficulty 2 of 9+20 XP
2.142Geometry
Locked
A cone from a paper sector
Difficulty 2 of 9+20 XP
2.143Combinatorics
Locked
Digit sum seven
Difficulty 2 of 9+20 XP
2.144Arithmetic
Locked
Painting a fence in pairs
Difficulty 2 of 9+20 XP
2.145Equations
Locked
To the cottage and back
Difficulty 2 of 9+20 XP
2.146Geometry
Locked
Crossed ropes
Difficulty 2 of 9+20 XP
2.147Combinatorics
Locked
How a tennis match can go
Difficulty 2 of 9+20 XP
2.148Logic
Locked
Guess my number
Difficulty 2 of 9+20 XP
2.149Arithmetic
Locked
Digit sum forty
Difficulty 2 of 9+20 XP
2.150Equations
Locked
Two ratios of one blend
Difficulty 2 of 9+20 XP
2.151Geometry
Locked
A perimeter from the hypotenuse and the height
Difficulty 2 of 9+20 XP
2.152Combinatorics
Locked
Where the seven appears
Difficulty 2 of 9+20 XP
2.153Arithmetic
Locked
Always two short
Difficulty 2 of 9+20 XP
2.154Algebra
Locked
A difference of squares equal to 120
Difficulty 2 of 9+20 XP
2.155Geometry
Locked
Top up the cone cup
Difficulty 2 of 9+20 XP
2.156Probability
Locked
One die against two
Difficulty 2 of 9+20 XP
2.157Arithmetic
Locked
Diluting juice
Difficulty 2 of 9+20 XP
2.158Equations
Locked
A boat and a raft on a river
Difficulty 2 of 9+20 XP
2.159Geometry
Locked
Two parallel chords
Difficulty 2 of 9+20 XP
2.160Logic
Locked
One of them is wrong
Difficulty 2 of 9+20 XP
2.161Arithmetic
Locked
The way to school
Difficulty 2 of 9+20 XP
2.162Algebra
Locked
One equation, two unknowns
Difficulty 2 of 9+20 XP
2.163Geometry
Locked
Two segments in a square
Difficulty 2 of 9+20 XP
2.164Combinatorics
Locked
Five friends on a bench
Difficulty 2 of 9+20 XP
2.165Arithmetic
Locked
Different digits and the divisor 72
Difficulty 2 of 9+20 XP
2.166Equations
Locked
A number read backwards
Difficulty 2 of 9+20 XP
2.167Geometry
Locked
Lattice points in a triangle
Difficulty 2 of 9+20 XP
2.168Probability
Locked
Five numbers with given statistics
Difficulty 2 of 9+20 XP
2.169Arithmetic
Locked
Two pipes and a tank
Difficulty 2 of 9+20 XP
2.170Algebra
Locked
Three numbers and their squares
Difficulty 2 of 9+20 XP
2.171Geometry
Locked
Three segments of equal length
Difficulty 2 of 9+20 XP
2.172Logic
Locked
A guaranteed sum
Difficulty 2 of 9+20 XP
3.1Calculus
Locked
Critical point
Difficulty 3 of 9+45 XP
3.2Combinatorics
Locked
Grid paths
Difficulty 3 of 9+45 XP
3.3Calculus
Locked
Infinite geometric series
Difficulty 3 of 9+45 XP
3.4Arithmetic
Locked
Remainder after division
Difficulty 3 of 9+45 XP
3.5Geometry
Locked
Cone volume
Difficulty 3 of 9+45 XP
3.6Equations
Locked
Biquadratic equation
Difficulty 3 of 9+45 XP
3.7Functions
Locked
Double composition
Difficulty 3 of 9+45 XP
3.8Probability
Locked
Even sum
Difficulty 3 of 9+45 XP
3.9Arithmetic
Locked
Trailing zeros of 25!
Difficulty 3 of 9+45 XP
3.10Calculus
Locked
A famous limit
Difficulty 3 of 9+45 XP
3.11Equations
Locked
Common base
Difficulty 3 of 9+45 XP
3.12Combinatorics
Locked
Two teams from eight
Difficulty 3 of 9+45 XP
3.13Calculus
Locked
Definite integral II
Difficulty 3 of 9+45 XP
3.14Arithmetic
Locked
Sum of squares 1 to 10
Difficulty 3 of 9+45 XP
3.15Equations
Locked
Unknown in base and exponent
Difficulty 3 of 9+45 XP
3.16Probability
Locked
Exactly three heads
Difficulty 3 of 9+45 XP

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All problems

Rational expressions and the year 2026

A cone from a paper sector

Digit sum seven

Painting a fence in pairs

To the cottage and back

Crossed ropes

How a tennis match can go

Guess my number

Digit sum forty

Two ratios of one blend

A perimeter from the hypotenuse and the height

Where the seven appears

Always two short

A difference of squares equal to 120

Top up the cone cup

One die against two

Diluting juice

A boat and a raft on a river

Two parallel chords

One of them is wrong

The way to school

One equation, two unknowns

Two segments in a square

Five friends on a bench

Different digits and the divisor 72

A number read backwards

Lattice points in a triangle

Five numbers with given statistics

Two pipes and a tank

Three numbers and their squares

Three segments of equal length

A guaranteed sum

Critical point

Grid paths

Infinite geometric series

Remainder after division

Cone volume

Biquadratic equation

Double composition

Even sum

Trailing zeros of 25!

A famous limit

Common base

Two teams from eight

Definite integral II

Sum of squares 1 to 10

Unknown in base and exponent

Exactly three heads