On a calculator, make 15 by using only the 2 key and any of the
four operations keys. How many ways can you find to do it?
Number problems at primary level to work on with others.
Find another number that is one short of a square number and when
you double it and add 1, the result is also a square number.
This number has 903 digits. What is the sum of all 903 digits?
On the table there is a pile of oranges and lemons that weighs
exactly one kilogram. Using the information, can you work out how
many lemons there are?
Number problems at primary level that require careful consideration.
What is happening at each box in these machines?
Can you score 100 by throwing rings on this board? Is there more
than way to do it?
Number problems at primary level that may require determination.
What do the digits in the number fifteen add up to? How many other
numbers have digits with the same total but no zeros?
Rocco ran in a 200 m race for his class. Use the information to
find out how many runners there were in the race and what Rocco's
finishing position was.
Amy has a box containing domino pieces but she does not think it is a complete set. She has 24 dominoes in her box and there are 125 spots on them altogether. Which of her domino pieces are missing?
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?
There are three buckets each of which holds a maximum of 5 litres.
Use the clues to work out how much liquid there is in each bucket.
Use the information to work out how many gifts there are in each
What is the sum of all the three digit whole numbers?
Try adding together the dates of all the days in one week. Now
multiply the first date by 7 and add 21. Can you explain what
Find the next number in this pattern: 3, 7, 19, 55 ...
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 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?
A game for 2 people. Use your skills of addition, subtraction, multiplication and division to blast the asteroids.
Use 4 four times with simple operations so that you get the answer 12. Can you make 15, 16 and 17 too?
This group activity will encourage you to share calculation strategies and to think about which strategy might be the most efficient.
Peter, Melanie, Amil and Jack received a total of 38 chocolate
eggs. Use the information to work out how many eggs each person
Use your logical reasoning to work out how many cows and how many
sheep there are in each field.
Annie cut this numbered cake into 3 pieces with 3 cuts so that the
numbers on each piece added to the same total. Where were the cuts
and what fraction of the whole cake was each piece?
In this investigation, you are challenged to make mobile phone
numbers which are easy to remember. What happens if you make a
sequence adding 2 each time?
This task combines spatial awareness with addition and multiplication.
EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.
Put operations signs between the numbers 3 4 5 6 to make the highest possible number and lowest possible number.
The clockmaker's wife cut up his birthday cake to look like a clock
face. Can you work out who received each piece?
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?
The value of the circle changes in each of the following problems. Can you discover its value in each problem?
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?
Got It game for an adult and child. How can you play so that you know you will always win?
Where can you draw a line on a clock face so that the numbers on
both sides have the same total?
Some Games That May Be Nice or Nasty for an adult and child. Use your knowledge of place value to beat your opponent.
If the numbers 5, 7 and 4 go into this function machine, what
numbers will come out?
Put a number at the top of the machine and collect a number at the
bottom. What do you get? Which numbers get back to themselves?
Who said that adding couldn't be fun?
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?
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 your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.
Place the digits 1 to 9 into the circles so that each side of the
triangle adds to the same total.
Can you draw a continuous line through 16 numbers on this grid so
that the total of the numbers you pass through is as high as
Tell your friends that you have a strange calculator that turns
numbers backwards. What secret number do you have to enter to make
141 414 turn around?
A game for 2 players. Practises subtraction or other maths
If the answer's 2010, what could the question be?
Ten cards are put into five envelopes so that there are two cards in each envelope. The sum of the numbers inside it is written on each envelope. What numbers could be inside the envelopes?
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?