Arrange the numbers 1 to 6 in each set of circles below. The sum of each side of the triangle should equal the number in its centre.
Can you go from A to Z right through the alphabet in the hexagonal maze?
Fill in the missing numbers so that adding each pair of corner numbers gives you the number between them (in the box).
On a farm there were some hens and sheep. Altogether there were 8 heads and 22 feet. How many hens were there?
On the planet Vuv there are two sorts of creatures. The Zios have 3 legs and the Zepts have 7 legs. The great planetary explorer Nico counted 52 legs. How many Zios and how many Zepts were there?
You have a set of the digits from 0 – 9. Can you arrange these in the five boxes to make two-digit numbers as close to the targets as possible?
Pat counts her sweets in different groups and both times she has some left over. How many sweets could she have had?
There are 78 prisoners in a square cell block of twelve cells. The clever prison warder arranged them so there were 25 along each wall of the prison block. How did he do it?
Kate has eight multilink cubes. She has two red ones, two yellow, two green and two blue. She wants to fit them together to make a cube so that each colour shows on each face just once.
Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.
The clockmaker's wife cut up his birthday cake to look like a clock face. Can you work out who received each piece?
In this problem it is not the squares that jump, you do the jumping! The idea is to go round the track in as few jumps as possible.
If these balls are put on a line with each ball touching the one in front and the one behind, which arrangement makes the shortest line of balls?
Place the digits 1 to 9 into the circles so that each side of the triangle adds to the same total.
There are 44 people coming to a dinner party. There are 15 square tables that seat 4 people. Find a way to seat the 44 people using all 15 tables, with no empty places.
Make one big triangle so the numbers that touch on the small triangles add to 10.
Can you see how these factor-multiple chains work? Find the chain which contains the smallest possible numbers. How about the largest possible numbers?
Nine squares with side lengths 1, 4, 7, 8, 9, 10, 14, 15, and 18 cm can be fitted together to form a rectangle. What are the dimensions of the rectangle?
How many starfish could there be on the beach, and how many children, if I can see 28 arms?
There are three baskets, a brown one, a red one and a pink one, holding a total of 10 eggs. Can you use the information given to find out how many eggs are in each basket?
I was looking at the number plate of a car parked outside. Using my special code S208VBJ adds to 65. Can you crack my code and use it to find out what both of these number plates add up to?
Use the three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
Using the numbers 1, 2, 3, 4 and 5 once and only once, and the operations x and ÷ once and only once, what is the smallest whole number you can make?
Throughout these challenges, the touching faces of any adjacent dice must have the same number. Can you find a way of making the total on the top come to each number from 11 to 18 inclusive?
Start by putting one million (1 000 000) into the display of your calculator. Can you reduce this to 7 using just the 7 key and add, subtract, multiply, divide and equals as many times as you like?
Can you make dice stairs using the rules stated? How do you know you have all the possible stairs?
Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.
Use the information to work out how many gifts there are in each pile.
The discs for this game are kept in a flat square box with a square hole for each. Use the information to find out how many discs of each colour there are in the box.
Can you draw a continuous line through 16 numbers on this grid so that the total of the numbers you pass through is as high as possible?
As you come down the ladders of the Tall Tower you collect useful spells. Which way should you go to collect the most spells?
A dog is looking for a good place to bury his bone. Can you work out where he started and ended in each case? What possible routes could he have taken?
Is it possible to draw a 5-pointed star without taking your pencil off the paper? Is it possible to draw a 6-pointed star in the same way without taking your pen off?
Can you use the information to find out which cards I have used?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
There are three versions of this challenge. The idea is to change the colour of all the spots on the grid. Can you do it in fewer throws of the dice?
You have two sets of the digits 0 – 9. Can you arrange these in the five boxes to make four-digit numbers as close to the target numbers as possible?
On the table there is a pile of oranges and lemons that weighs exactly one kilogram. Using the information, can you work out how many lemons there are?
All the girls would like a puzzle each for Christmas and all the boys would like a book each. Solve the riddle to find out how many puzzles and books Santa left.
Peter, Melanie, Amil and Jack received a total of 38 chocolate eggs. Use the information to work out how many eggs each person had.
Rocco ran in a 200 m race for his class. Use the information to find out how many runners there were in the race and what Rocco's finishing position was.
Work out Tom's number from the answers he gives his friend. He will only answer 'yes' or 'no'.
Cassandra, David and Lachlan are brothers and sisters. They range in age between 1 year and 14 years. Can you figure out their exact ages from the clues?
Using only six straight cuts, find a way to make as many pieces of pizza as possible. (The pieces can be different sizes and shapes).
56 406 is the product of two consecutive numbers. What are these two numbers?
Find another number that is one short of a square number and when you double it and add 1, the result is also a square number.
In this problem you have to place four by four magic squares on the faces of a cube so that along each edge of the cube the numbers match.
Your challenge is to find the longest way through the network following this rule. You can start and finish anywhere, and with any shape, as long as you follow the correct order.
Find out why these matrices are magic. Can you work out how they were made? Can you make your own Magic Matrix?
Using the statements, can you work out how many of each type of rabbit there are in these pens?