Search by Topic

Resources tagged with Addition & subtraction similar to Square Subtraction:

Filter by: Content type:
Stage:
Challenge level: Challenge Level:1 Challenge Level:2 Challenge Level:3

There are 231 results

Broad Topics > Calculations and Numerical Methods > Addition & subtraction

problem icon

Take Three Numbers

Stage: 2 Challenge Level: Challenge Level:1

What happens when you add three numbers together? Will your answer be odd or even? How do you know?

problem icon

Arrange the Digits

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

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?

problem icon

Six Is the Sum

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

What do the digits in the number fifteen add up to? How many other numbers have digits with the same total but no zeros?

problem icon

A Mixed-up Clock

Stage: 2 Challenge Level: Challenge Level:1

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?

problem icon

Adding Plus

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you put plus signs in so this is true? 1 2 3 4 5 6 7 8 9 = 99 How many ways can you do it?

problem icon

Rabbits in the Pen

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Using the statements, can you work out how many of each type of rabbit there are in these pens?

problem icon

Oh! Harry!

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

A group of children are using measuring cylinders but they lose the labels. Can you help relabel them?

problem icon

Four Goodness Sake

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Use 4 four times with simple operations so that you get the answer 12. Can you make 15, 16 and 17 too?

problem icon

Number Differences

Stage: 2 Challenge Level: Challenge Level:1

Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd. How many different ways can you do this?

problem icon

Oddly

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Find the sum of all three-digit numbers each of whose digits is odd.

problem icon

Hot Pursuit

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

The sum of the first 'n' natural numbers is a 3 digit number in which all the digits are the same. How many numbers have been summed?

problem icon

Cows and Sheep

Stage: 2 Challenge Level: Challenge Level:1

Use your logical reasoning to work out how many cows and how many sheep there are in each field.

problem icon

Alphabet Soup

Stage: 3 Challenge Level: Challenge Level:1

This challenge is to make up YOUR OWN alphanumeric. Each letter represents a digit and where the same letter appears more than once it must represent the same digit each time.

problem icon

Add the Weights

Stage: 2 Challenge Level: Challenge Level:1

If you have only four weights, where could you place them in order to balance this equaliser?

problem icon

Magic Vs

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?

problem icon

Dicey Addition

Stage: 1 and 2 Challenge Level: Challenge Level:1

Who said that adding couldn't be fun?

problem icon

The Deca Tree

Stage: 2 Challenge Level: Challenge Level:1

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.

problem icon

A-magical Number Maze

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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!

problem icon

Sam's Quick Sum

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

What is the sum of all the three digit whole numbers?

problem icon

More Carroll Diagrams

Stage: 2 Challenge Level: Challenge Level:1

How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?

problem icon

On Target

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

You have 5 darts and your target score is 44. How many different ways could you score 44?

problem icon

All Seated

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Look carefully at the numbers. What do you notice? Can you make another square using the numbers 1 to 16, that displays the same properties?

problem icon

Largest Number

Stage: 3 Challenge Level: Challenge Level:1

What is the largest number you can make using the three digits 2, 3 and 4 in any way you like, using any operations you like? You can only use each digit once.

problem icon

Number Tracks

Stage: 2 Challenge Level: Challenge Level:1

Ben’s class were cutting up number tracks. First they cut them into twos and added up the numbers on each piece. What patterns could they see?

problem icon

Calendar Calculations

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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 happens?

problem icon

How Much Did it Cost?

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Use your logical-thinking skills to deduce how much Dan's crisps and ice-cream cost altogether.

problem icon

Napier's Bones

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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?

problem icon

Arranging the Tables

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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.

problem icon

The Pied Piper of Hamelin

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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!

problem icon

Page Numbers

Stage: 2 Short Challenge Level: Challenge Level:1

Exactly 195 digits have been used to number the pages in a book. How many pages does the book have?

problem icon

Odds and Threes

Stage: 2 Challenge Level: Challenge Level:1

A game for 2 people using a pack of cards Turn over 2 cards and try to make an odd number or a multiple of 3.

problem icon

Finding Fifteen

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Tim had nine cards each with a different number from 1 to 9 on it. How could he have put them into three piles so that the total in each pile was 15?

problem icon

One Million to Seven

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

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?

problem icon

Hubble, Bubble

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Winifred Wytsh bought a box each of jelly babies, milk jelly bears, yellow jelly bees and jelly belly beans. In how many different ways could she make a jolly jelly feast with 32 legs?

problem icon

Polo Square

Stage: 2 Challenge Level: Challenge Level:1

Arrange eight of the numbers between 1 and 9 in the Polo Square below so that each side adds to the same total.

problem icon

Zargon Glasses

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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?

problem icon

Prison Cells

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

There are 78 prisoners in a square cell block of twelve cells. The clever prison warder arranged them so there were 25 along each wall of the prison block. How did he do it?

problem icon

The Puzzling Sweet Shop

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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?

problem icon

Reach 100

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

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.

problem icon

The 24 Game

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

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?

problem icon

Journeys in Numberland

Stage: 2 Challenge Level: Challenge Level:1

Tom and Ben visited Numberland. Use the maps to work out the number of points each of their routes scores.

problem icon

The Dice Train

Stage: 2 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

This dice train has been made using specific rules. How many different trains can you make?

problem icon

X Is 5 Squares

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you arrange 5 different digits (from 0 - 9) in the cross in the way described?

problem icon

Today's Date - 01/06/2009

Stage: 1 and 2 Challenge Level: Challenge Level:1

What do you notice about the date 03.06.09? Or 08.01.09? This challenge invites you to investigate some interesting dates yourself.

problem icon

A Dotty Problem

Stage: 2 Challenge Level: Challenge Level:1

Starting with the number 180, take away 9 again and again, joining up the dots as you go. Watch out - don't join all the dots!

problem icon

How Old?

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Cherri, Saxon, Mel and Paul are friends. They are all different ages. Can you find out the age of each friend using the information?

problem icon

I'm Eight

Stage: 1, 2, 3 and 4 Challenge Level: Challenge Level:1

Find a great variety of ways of asking questions which make 8.

problem icon

Dice and Spinner Numbers

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

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?

problem icon

Doplication

Stage: 2 Challenge Level: Challenge Level:1

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?

problem icon

Sums and Differences 2

Stage: 2 Challenge Level: Challenge Level:1

Find the sum and difference between a pair of two-digit numbers. Now find the sum and difference between the sum and difference! What happens?