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#### Resources tagged with Addition & subtraction similar to Magic Triangle:

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### Magic Triangle

##### Age 7 to 11 Challenge Level:

Place the digits 1 to 9 into the circles so that each side of the triangle adds to the same total.

### Super Value Shapes

##### Age 7 to 11 Challenge Level:

If each of these three shapes has a value, can you find the totals of the combinations? Perhaps you can use the shapes to make the given totals?

### Rod Measures

##### Age 7 to 11 Challenge Level:

Using 3 rods of integer lengths, none longer than 10 units and not using any rod more than once, you can measure all the lengths in whole units from 1 to 10 units. How many ways can you do this?

### One Wasn't Square

##### Age 7 to 11 Challenge Level:

Mrs Morgan, the class's teacher, pinned numbers onto the backs of three children. Use the information to find out what the three numbers were.

### Napier's Bones

##### Age 7 to 11 Challenge Level:

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?

### Sam's Quick Sum

##### Age 7 to 11 Challenge Level:

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

### Totality

##### Age 5 to 11 Challenge Level:

This is an adding game for two players.

### The Clockmaker's Birthday Cake

##### Age 7 to 11 Challenge Level:

The clockmaker's wife cut up his birthday cake to look like a clock face. Can you work out who received each piece?

### 1, 2, 3 Magic Square

##### Age 7 to 11 Challenge Level:

Arrange three 1s, three 2s and three 3s in this square so that every row, column and diagonal adds to the same total.

### The Deca Tree

##### Age 7 to 11 Challenge Level:

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 24 Game

##### Age 7 to 11 Challenge Level:

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?

### Number Juggle

##### Age 7 to 11 Challenge Level:

Fill in the missing numbers so that adding each pair of corner numbers gives you the number between them (in the box).

### How Do You Do It?

##### Age 7 to 11 Challenge Level:

This group activity will encourage you to share calculation strategies and to think about which strategy might be the most efficient.

### Cherries Come in Twos

##### Age 7 to 11 Challenge Level:

Susie took cherries out of a bowl by following a certain pattern. How many cherries had there been in the bowl to start with if she was left with 14 single ones?

### Journeys

##### Age 7 to 11 Challenge Level:

Investigate the different distances of these car journeys and find out how long they take.

### I'm Eight

##### Age 5 to 11 Challenge Level:

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

### Calendar Calculations

##### Age 7 to 11 Challenge Level:

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?

### Magic Circles

##### Age 7 to 11 Challenge Level:

Put the numbers 1, 2, 3, 4, 5, 6 into the squares so that the numbers on each circle add up to the same amount. Can you find the rule for giving another set of six numbers?

### Christmas Shopping

##### Age 7 to 11 Challenge Level:

Vera is shopping at a market with these coins in her purse. Which things could she give exactly the right amount for?

### Throw a 100

##### Age 7 to 11 Challenge Level:

Can you score 100 by throwing rings on this board? Is there more than way to do it?

### Bean Bags for Bernard's Bag

##### Age 7 to 11 Challenge Level:

How could you put eight beanbags in the hoops so that there are four in the blue hoop, five in the red and six in the yellow? Can you find all the ways of doing this?

### Arranging the Tables

##### Age 7 to 11 Challenge Level:

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.

### Clever Keys

##### Age 7 to 11 Short Challenge Level:

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?

### Zios and Zepts

##### Age 7 to 11 Challenge Level:

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?

### Sisters and Brothers

##### Age 7 to 11 Challenge Level:

Cassandra, David and Lachlan are brothers and sisters. They range in age between 1 year and 14 years. Can you figure out their exact ages from the clues?

### Maze 100

##### Age 7 to 11 Challenge Level:

Can you go through this maze so that the numbers you pass add to exactly 100?

### Reverse Trick

##### Age 7 to 11 Challenge Level:

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?

### Rocco's Race

##### Age 7 to 11 Short Challenge Level:

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.

### Pouring the Punch Drink

##### Age 7 to 11 Challenge Level:

There are 4 jugs which hold 9 litres, 7 litres, 4 litres and 2 litres. Find a way to pour 9 litres of drink from one jug to another until you are left with exactly 3 litres in three of the jugs.

### Code Breaker

##### Age 7 to 11 Challenge Level:

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?

### Buckets of Thinking

##### Age 7 to 11 Challenge Level:

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.

### Machines

##### Age 7 to 11 Challenge Level:

What is happening at each box in these machines?

##### Age 7 to 11 Challenge Level:

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?

### A-magical Number Maze

##### Age 7 to 11 Challenge Level:

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!

### Oranges and Lemons

##### Age 7 to 11 Challenge Level:

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?

### Dividing a Cake

##### Age 7 to 11 Challenge Level:

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?

### Clock Face

##### Age 7 to 11 Challenge Level:

Where can you draw a line on a clock face so that the numbers on both sides have the same total?

### On Target

##### Age 7 to 11 Challenge Level:

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

### Rabbits in the Pen

##### Age 7 to 11 Challenge Level:

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

### Build it up More

##### Age 7 to 11 Challenge Level:

This task follows on from Build it Up and takes the ideas into three dimensions!

### Strike it Out for Two

##### Age 5 to 11 Challenge Level:

Strike it Out game for an adult and child. Can you stop your partner from being able to go?

### Sums and Differences 2

##### Age 7 to 11 Challenge Level:

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?

### Sums and Differences 1

##### Age 7 to 11 Challenge Level:

This challenge focuses on finding the sum and difference of pairs of two-digit numbers.

### Some Secret Codes

##### Age 7 to 11 Challenge Level:

Can you follow the rule to decode the messages?

##### Age 7 to 11 Challenge Level:

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.

### It Was 2010!

##### Age 5 to 11 Challenge Level:

If the answer's 2010, what could the question be?

### Which Symbol?

##### Age 7 to 11 Challenge Level:

Choose a symbol to put into the number sentence.

### Six Is the Sum

##### Age 7 to 11 Challenge Level:

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

### Next Number

##### Age 7 to 11 Short Challenge Level:

Find the next number in this pattern: 3, 7, 19, 55 ...

### Being Resilient - Primary Number

##### Age 5 to 11 Challenge Level:

Number problems at primary level that may require resilience.