5 by 5 Mathdokus
Two and Two
How many solutions can you find to this sum? Each of the different letters stands for a different number.
Consecutive Numbers
Missing Multipliers
Fruity Totals
The Number Jumbler
Sticky Numbers
Funny Factorisation
How Many Miles To Go?
Squares in rectangles
How steep is the slope?
On the grid provided, we can draw lines with different gradients. How many different gradients can you find? Can you arrange them in order of steepness?
Farey Sequences
Parallelogram It
Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a parallelogram.
Product Sudoku
Going round in circles
Where can we visit?
Forwards Add Backwards
Number Pyramids
Try entering different sets of numbers in the number pyramids. How does the total at the top change?
Factors and Multiples Puzzle
Shifting Times Tables
Can you find a way to identify times tables after they have been shifted up or down?
Nine Colours
Overlaps
Peaches today, Peaches tomorrow...
River Crossing
Charlie's delightful machine
Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?
Ben's Game
Consecutive negative numbers
Sociable Cards
Number Daisy
Growing Surprises
Cuboids
Weights
American Billions
Completing Quadrilaterals
We started drawing some quadrilaterals - can you complete them?
Square It
Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a square.
Days and Dates
An Equilateral Triangular Problem
Take an equilateral triangle and cut it into smaller pieces. What can you do with them?
Consecutive Seven
M, M and M
If you are given the mean, median and mode of five positive whole numbers, can you find the numbers?
Opposite vertices
Can you recreate squares and rhombuses if you are only given a side or a diagonal?
1 Step 2 Step
Gabriel's Problem
Fence it
Elevenses
Counting Factors
What's it worth?
Can you Make 100?
Isosceles Triangles
Can they be equal?
Summing Consecutive Numbers
Shopping Basket
Alison's quilt
Stars
Power mad!
Triangles to Tetrahedra
Shapely pairs
A game in which players take it in turns to turn up two cards. If they can draw a triangle which satisfies both properties they win the pair of cards. And a few challenging questions to follow...
Multiples Sudoku
Magic Letters
Cinema Problem
How far does it move?
Experiment with the interactivity of "rolling" regular polygons, and explore how the different positions of the dot affects the distance it travels at each stage.
Keep it simple
Wipeout
Speeding up, slowing down
Experiment with the interactivity of "rolling" regular polygons, and explore how the different positions of the dot affects its speed at each stage.
Shady Symmetry
Up and across
Experiment with the interactivity of "rolling" regular polygons, and explore how the different positions of the dot affects its vertical and horizontal movement at each stage.
Warmsnug Double Glazing
What's Possible?
Matchless
Partly Painted Cube
Parabolic Patterns
The illustration shows the graphs of fifteen functions. Two of them have equations $y=x^2$ and $y=-(x-4)^2$. Find the equations of all the other graphs.
Painted Cube
Which is cheaper?
LCM Sudoku
Training schedule
CD Heaven
Finding factors
Nutrition and Cycling
Expenses
Symmetricality
Pick's Theorem
Surprising Transformations
I took the graph y=4x+7 and performed four transformations. Can you find the order in which I could have carried out the transformations?