Explore Alex's number plumber. What questions would you like to ask? What do you think is happening to the numbers?
Find the product of the numbers on the routes from A to B. Which route has the smallest product? Which the largest?
Can you fill in this table square? The numbers 2 -12 were used to generate it with just one number used twice.
Can you arrange 5 different digits (from 0 - 9) in the cross in the way described?
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.
Can you design a new shape for the twenty-eight squares and arrange the numbers in a logical way? What patterns do you notice?
If the answer's 2010, what could the question be?
How would you count the number of fingers in these pictures?
Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?
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?
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?
Tom and Ben visited Numberland. Use the maps to work out the number of points each of their routes scores.
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!
Look on the back of any modern book and you will find an ISBN code. Take this code and calculate this sum in the way shown. Can you see what the answers always have in common?
Put operations signs between the numbers 3 4 5 6 to make the highest possible number and lowest possible number.
Claire thinks she has the most sports cards in her album. "I have 12 pages with 2 cards on each page", says Claire. Ross counts his cards. "No! I have 3 cards on each of my pages and there are. . . .
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 multiplication uses each of the digits 0 - 9 once and once only. Using the information given, can you replace the stars in the calculation with figures?
Explore Alex's number plumber. What questions would you like to ask? Don't forget to keep visiting NRICH projects site for the latest developments and questions.
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?
What is happening at each box in these machines?
Skippy and Anna are locked in a room in a large castle. The key to that room, and all the other rooms, is a number. The numbers are locked away in a problem. Can you help them to get out?
Find at least one way to put in some operation signs (+ - x ÷) to make these digits come to 100.
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?
Where can you draw a line on a clock face so that the numbers on both sides have the same total?
On my calculator I divided one whole number by another whole number and got the answer 3.125. If the numbers are both under 50, what are they?
Can you work out how many flowers there will be on the Amazing Splitting Plant after it has been growing for six weeks?
Well now, what would happen if we lost all the nines in our number system? Have a go at writing the numbers out in this way and have a look at the multiplications table.
There were 22 legs creeping across the web. How many flies? How many spiders?
EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.
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?
Here are the prices for 1st and 2nd class mail within the UK. You have an unlimited number of each of these stamps. Which stamps would you need to post a parcel weighing 825g?
Use your logical reasoning to work out how many cows and how many sheep there are in each field.
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?
Using the statements, can you work out how many of each type of rabbit there are in these pens?
These sixteen children are standing in four lines of four, one behind the other. They are each holding a card with a number on it. Can you work out the missing numbers?
This number has 903 digits. What is the sum of all 903 digits?
This task combines spatial awareness with addition and multiplication.
An old game but lots of arithmetic!
Number problems at primary level that require careful consideration.
Number problems at primary level that may require resilience.
If the numbers 5, 7 and 4 go into this function machine, what numbers will come out?
What do you notice about the date 03.06.09? Or 08.01.09? This challenge invites you to investigate some interesting dates yourself.
These eleven shapes each stand for a different number. Can you use the multiplication sums to work out what they are?
Use your logical-thinking skills to deduce how much Dan's crisps and ice-cream cost altogether.
This group activity will encourage you to share calculation strategies and to think about which strategy might be the most efficient.
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.
A game for 2 people. Use your skills of addition, subtraction, multiplication and division to blast the asteroids.
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?
Go through the maze, collecting and losing your money as you go. Which route gives you the highest return? And the lowest?