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?
Becky created a number plumber which multiplies by 5 and subtracts
4. What do you notice about the numbers that it produces? Can you
explain your findings?
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.
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?
Each child in Class 3 took four numbers out of the bag. Who had
made the highest even number?
Number problems at primary level that may require determination.
Find the sum of all three-digit numbers each of whose digits is
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Can you arrange the digits 1,2,3,4,5,6,7,8,9 into three 3-digit
numbers such that their total is close to 1500?
Who said that adding couldn't be fun?
This activity involves rounding four-digit numbers to the nearest thousand.
A school song book contains 700 songs. The numbers of the songs are displayed by combining special small single-digit boards. What is the minimum number of small boards that is needed?
What is the sum of all the digits in all the integers from one to
Follow the clues to find the mystery number.
What do the digits in the number fifteen add up to? How many other
numbers have digits with the same total but no zeros?
Number problems at primary level that require careful consideration.
Number problems at primary level to work on with others.
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?
Explore the relationship between simple linear functions and their
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?
A church hymn book contains 700 hymns. The numbers of the hymns are
displayed by combining special small single-digit boards. What is
the minimum number of small boards that is needed?
Using balancing scales what is the least number of weights needed
to weigh all integer masses from 1 to 1000? Placing some of the
weights in the same pan as the object how many are needed?
Can you complete this calculation by filling in the missing numbers? In how many different ways can you do it?
In the multiplication calculation, some of the digits have been replaced by letters and others by asterisks. Can you reconstruct the original multiplication?
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 replace the letters with numbers? Is there only one solution in each case?
Can you work out some different ways to balance this equation?
Some Games That May Be Nice or Nasty for an adult and child. Use your knowledge of place value to beat your opponent.
This is a game in which your counters move in a spiral round the snail's shell. It is about understanding tens and units.
Replace each letter with a digit to make this addition correct.
Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?
How many six digit numbers are there which DO NOT contain a 5?
Use two dice to generate two numbers with one decimal place. What happens when you round these numbers to the nearest whole number?
Number problems for inquiring primary learners.
When the number x 1 x x x is multiplied by 417 this gives the
answer 9 x x x 0 5 7. Find the missing digits, each of which is
represented by an "x" .
Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?
This addition sum uses all ten digits 0, 1, 2...9 exactly once.
Find the sum and show that the one you give is the only
The number 3723(in base 10) is written as 123 in another base. What
is that base?
Have a go at balancing this equation. Can you find different ways of doing it?
Can you substitute numbers for the letters in these sums?
Choose any 3 digits and make a 6 digit number by repeating the 3
digits in the same order (e.g. 594594). Explain why whatever digits
you choose the number will always be divisible by 7, 11 and 13.
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?
There are six numbers written in five different scripts. Can you sort out which is which?
What happens when you round these three-digit numbers to the nearest 100?
Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...
A three digit number abc is always divisible by 7 when 2a+3b+c is divisible by 7. Why?
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
Amazing as it may seem the three fives remaining in the following
`skeleton' are sufficient to reconstruct the entire long division
This article, written for teachers, looks at the different kinds of
recordings encountered in Primary Mathematics lessons and the
importance of not jumping to conclusions!
What happens when you round these numbers to the nearest whole number?