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There are 133 NRICH Mathematical resources connected to Place value, you may find related items under Place value and the number system.
Broad Topics > Place value and the number system > Place valueThe Number Jumbler can always work out your chosen symbol. Can you work out how?
Try out this number trick. What happens with different starting numbers? What do you notice?
Who said that adding, subtracting, multiplying and dividing couldn't be fun?
Where should you start, if you want to finish back where you started?
What happens when you add a three digit number to its reverse?
By selecting digits for an addition grid, what targets can you make?
Try out some calculations. Are you surprised by the results?
Have a go at balancing this equation. Can you find different ways of doing it?
Use two dice to generate two numbers with one decimal place. What happens when you round these numbers to the nearest whole number?
What happens when you round these three-digit numbers to the nearest 100?
What happens when you round these numbers to the nearest whole number?
Can you work out some different ways to balance this equation?
Can you complete this calculation by filling in the missing numbers? In how many different ways can you do it?
What two-digit numbers can you make with these two dice? What can't you make?
In this game, you throw a dice and move counters along the snail's body and in a spiral around the snail's shell. It is about understanding tens and ones.
Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?
Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?
These spinners will give you the tens and unit digits of a number. Can you choose sets of numbers to collect so that you spin six numbers belonging to your sets in as few spins as possible?
Who said that adding, subtracting, multiplying and dividing couldn't be fun?
There are nasty versions of this dice game but we'll start with the nice ones...
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
You have a set of the digits from 0 to 9. Can you arrange these in the five boxes to make two-digit numbers as close to the targets as possible?
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?
Four of these clues are needed to find the chosen number on this grid and four are true but do nothing to help in finding the number. Can you sort out the clues and find the number?
Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?
In this 100 square, look at the green square which contains the numbers 2, 3, 12 and 13. What is the sum of the numbers that are diagonally opposite each other? What do you notice?
Do you agree with Badger's statements? Is Badger's reasoning 'watertight'? Why or why not?
How many more miles must the car travel before the numbers on the milometer and the trip meter contain the same digits in the same order?
Can you show that 1^99 + 2^99 + 3^99 + 4^99 + 5^99 is divisible by 5?
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.
Can you replace the letters with numbers? Is there only one solution in each case?
Evaluate these powers of 67. What do you notice? Can you convince someone what the answer would be to (a million sixes followed by a 7) squared?
How many six digit numbers are there which DO NOT contain a 5?
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Think of two whole numbers under 10, and follow the steps. I can work out both your numbers very quickly. How?
Choose four different digits from 1-9 and put one in each box so that the resulting four two-digit numbers add to a total of 100.
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?
Can you produce convincing arguments that a selection of statements about numbers are true?
How many solutions can you find to this sum? Each of the different letters stands for a different number.
There are six numbers written in five different scripts. Can you sort out which is which?
Can you explain the surprising results Jo found when she calculated the difference between square numbers?
Take any four digit number. Move the first digit to the end and move the rest along. Now add your two numbers. Did you get a multiple of 11?
Three people chose this as a favourite problem. It is the sort of problem that needs thinking time - but once the connection is made it gives access to many similar ideas.
A 2-Digit number is squared. When this 2-digit number is reversed and squared, the difference between the squares is also a square. What is the 2-digit number?
Can you create a Latin Square from multiples of a six digit number?
Lee was writing all the counting numbers from 1 to 20. She stopped for a rest after writing seventeen digits. What was the last number she wrote?
If you put three beads onto a tens/ones abacus you can make the numbers 3, 30, 12 or 21. What numbers can be made with six beads?