The heptathlon is an athletics competition consisting of 7 events. Can you make sense of the scoring system in order to advise a heptathlete on the best way to reach her target?
However did we manage before calculators? Is there an efficient way to do a square root if you have to do the work yourself?
A little bit of algebra explains this 'magic'. Ask a friend to pick 3 consecutive numbers and to tell you a multiple of 3. Then ask them to add the four numbers and multiply by 67, and to tell you. . . .
If a sum invested gains 10% each year how long before it has doubled its value?
Make some loops out of regular hexagons. What rules can you discover?
Jo has three numbers which she adds together in pairs. When she does this she has three different totals: 11, 17 and 22 What are the three numbers Jo had to start with?”
Many numbers can be expressed as the difference of two perfect squares. What do you notice about the numbers you CANNOT make?
Think of two whole numbers under 10, and follow the steps. I can work out both your numbers very quickly. How?
Think of a number and follow my instructions. Tell me your answer, and I'll tell you what you started with! Can you explain how I know?
Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?
Choose any four consecutive even numbers. Multiply the two middle numbers together. Multiply the first and last numbers. Now subtract your second answer from the first. Try it with your own. . . .
Create some shapes by combining two or more rectangles. What can you say about the areas and perimeters of the shapes you can make?
A job needs three men but in fact six people do it. When it is finished they are all paid the same. How much was paid in total, and much does each man get if the money is shared as Fred suggests?
Can you explain how this card trick works?
Here are three 'tricks' to amaze your friends. But the really clever trick is explaining to them why these 'tricks' are maths not magic. Like all good magicians, you should practice by trying. . . .
How to build your own magic squares.
Choose four consecutive whole numbers. Multiply the first and last numbers together. Multiply the middle pair together. What do you notice?
Pick a square within a multiplication square and add the numbers on each diagonal. What do you notice?
Write down a three-digit number Change the order of the digits to get a different number Find the difference between the two three digit numbers Follow the rest of the instructions then try. . . .
Can you show that you can share a square pizza equally between two people by cutting it four times using vertical, horizontal and diagonal cuts through any point inside the square?
Account of an investigation which starts from the area of an annulus and leads to the formula for the difference of two squares.
Can you find rectangles where the value of the area is the same as the value of the perimeter?
The diagram illustrates the formula: 1 + 3 + 5 + ... + (2n - 1) = n² Use the diagram to show that any odd number is the difference of two squares.
Think of a number, add one, double it, take away 3, add the number you first thought of, add 7, divide by 3 and take away the number you first thought of. You should now be left with 2. How do I. . . .
A task which depends on members of the group noticing the needs of others and responding.
Can you explain why a sequence of operations always gives you perfect squares?
A box has faces with areas 3, 12 and 25 square centimetres. What is the volume of the box?
What is the total number of squares that can be made on a 5 by 5 geoboard?
Sets of integers like 3, 4, 5 are called Pythagorean Triples, because they could be the lengths of the sides of a right-angled triangle. Can you find any more?
Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...
If the sides of the triangle in the diagram are 3, 4 and 5, what is the area of the shaded square?
Two motorboats travelling up and down a lake at constant speeds leave opposite ends A and B at the same instant, passing each other, for the first time 600 metres from A, and on their return, 400. . . .
Pick the number of times a week that you eat chocolate. This number must be more than one but less than ten. Multiply this number by 2. Add 5 (for Sunday). Multiply by 50... Can you explain why it. . . .
Can you use the diagram to prove the AM-GM inequality?
Polygons drawn on square dotty paper have dots on their perimeter (p) and often internal (i) ones as well. Find a relationship between p, i and the area of the polygons.
How many winning lines can you make in a three-dimensional version of noughts and crosses?
Arrange the numbers 1 to 16 into a 4 by 4 array. Choose a number. Cross out the numbers on the same row and column. Repeat this process. Add up you four numbers. Why do they always add up to 34?
The Number Jumbler can always work out your chosen symbol. Can you work out how?
Brian swims at twice the speed that a river is flowing, downstream from one moored boat to another and back again, taking 12 minutes altogether. How long would it have taken him in still water?
The squares of any 8 consecutive numbers can be arranged into two sets of four numbers with the same sum. True of false?
This article explains how to make your own magic square to mark a special occasion with the special date of your choice on the top line.
Some students have been working out the number of strands needed for different sizes of cable. Can you make sense of their solutions?
Attach weights of 1, 2, 4, and 8 units to the four attachment points on the bar. Move the bar from side to side until you find a balance point. Is it possible to predict that position?
Find some examples of pairs of numbers such that their sum is a factor of their product. eg. 4 + 12 = 16 and 4 × 12 = 48 and 16 is a factor of 48.
Try entering different sets of numbers in the number pyramids. How does the total at the top change?
Robert noticed some interesting patterns when he highlighted square numbers in a spreadsheet. Can you prove that the patterns will continue?
Jo made a cube from some smaller cubes, painted some of the faces of the large cube, and then took it apart again. 45 small cubes had no paint on them at all. How many small cubes did Jo use?
When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...
How could Penny, Tom and Matthew work out how many chocolates there are in different sized boxes?
The sums of the squares of three related numbers is also a perfect square - can you explain why?