This problem is based on the story of the Pied Piper of Hamelin. Investigate the different numbers of people and rats there could have been if you know how many legs there are altogether!
Using the statements, can you work out how many of each type of rabbit there are in these pens?
Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?
This magic square has operations written in it, to make it into a maze. Start wherever you like, go through every cell and go out a total of 15!
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.
Can you arrange 5 different digits (from 0 - 9) in the cross in the way described?
Use the information about Sally and her brother to find out how many children there are in the Brown family.
Katie had a pack of 20 cards numbered from 1 to 20. She arranged the cards into 6 unequal piles where each pile added to the same total. What was the total and how could this be done?
Find the product of the numbers on the routes from A to B. Which route has the smallest product? Which the largest?
What do you notice about the date 03.06.09? Or 08.01.09? This challenge invites you to investigate some interesting dates yourself.
Can you fill in this table square? The numbers 2 -12 were used to generate it with just one number used twice.
Use your logical-thinking skills to deduce how much Dan's crisps and ice-cream cost altogether.
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?
Can you find which shapes you need to put into the grid to make the totals at the end of each row and the bottom of each column?
This problem is based on a code using two different prime numbers less than 10. You'll need to multiply them together and shift the alphabet forwards by the result. Can you decipher the code?
There were chews for 2p, mini eggs for 3p, Chocko bars for 5p and lollypops for 7p in the sweet shop. What could each of the children buy with their money?
Cherri, Saxon, Mel and Paul are friends. They are all different ages. Can you find out the age of each friend using the information?
Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?
Imagine a pyramid which is built in square layers of small cubes. If we number the cubes from the top, starting with 1, can you picture which cubes are directly below this first cube?
Zumf makes spectacles for the residents of the planet Zargon, who have either 3 eyes or 4 eyes. How many lenses will Zumf need to make all the different orders for 9 families?
A group of children are using measuring cylinders but they lose the labels. Can you help relabel them?
At the beginning of May Tom put his tomato plant outside. On the same day he sowed a bean in another pot. When will the two be the same height?
The Man is much smaller than us. Can you use the picture of him next to a mug to estimate his height and how much tea he drinks?
This article for teachers describes how modelling number properties involving multiplication using an array of objects not only allows children to represent their thinking with concrete materials,. . . .
A game for 2 people. Use your skills of addition, subtraction, multiplication and division to blast the asteroids.
Twizzle, a female giraffe, needs transporting to another zoo. Which route will give the fastest journey?
Explore Alex's number plumber. What questions would you like to ask? What do you think is happening to the numbers?
Can you work out how many flowers there will be on the Amazing Splitting Plant after it has been growing for six weeks?
Throw the dice and decide whether to double or halve the number. Will you be the first to reach the target?
Can you work out the arrangement of the digits in the square so that the given products are correct? The numbers 1 - 9 may be used once and once only.
There were 22 legs creeping across the web. How many flies? How many spiders?
Find out what a Deca Tree is and then work out how many leaves there will be after the woodcutter has cut off a trunk, a branch, a twig and a leaf.
Use 4 four times with simple operations so that you get the answer 12. Can you make 15, 16 and 17 too?
Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?
Ahmed is making rods using different numbers of cubes. Which rod is twice the length of his first rod?
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?
There is a clock-face where the numbers have become all mixed up. Can you find out where all the numbers have got to from these ten statements?
The Scot, John Napier, invented these strips about 400 years ago to help calculate multiplication and division. Can you work out how to use Napier's bones to find the answer to these multiplications?
What happens when you add the digits of a number then multiply the result by 2 and you keep doing this? You could try for different numbers and different rules.
If the answer's 2010, what could the question be?
Choose a symbol to put into the number sentence.
The clockmaker's wife cut up his birthday cake to look like a clock face. Can you work out who received each piece?
In a Magic Square all the rows, columns and diagonals add to the 'Magic Constant'. How would you change the magic constant of this square?
Can you each work out the number on your card? What do you notice? How could you sort the cards?
If you had any number of ordinary dice, what are the possible ways of making their totals 6? What would the product of the dice be each time?
These eleven shapes each stand for a different number. Can you use the multiplication sums to work out what they are?
We can arrange dots in a similar way to the 5 on a dice and they usually sit quite well into a rectangular shape. How many altogether in this 3 by 5? What happens for other sizes?
Number problems at primary level that require careful consideration.
There are over sixty different ways of making 24 by adding, subtracting, multiplying and dividing all four numbers 4, 6, 6 and 8 (using each number only once). How many can you find?
Annie and Ben are playing a game with a calculator. What was Annie's secret number?