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Resources tagged with Combinations similar to Two Egg Timers:

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Broad Topics > Decision Mathematics and Combinatorics > Combinations

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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?

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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?

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Two Egg Timers

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

You have two egg timers. One takes 4 minutes exactly to empty and the other takes 7 minutes. What times in whole minutes can you measure and how?

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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?

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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.

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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?

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Elf Suits

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

If these elves wear a different outfit every day for as many days as possible, how many days can their fun last?

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Room Doubling

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

Investigate the different ways you could split up these rooms so that you have double the number.

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Ice Cream

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

You cannot choose a selection of ice cream flavours that includes totally what someone has already chosen. Have a go and find all the different ways in which seven children can have ice cream.

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Button-up Some More

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

How many ways can you find to do up all four buttons on my coat? How about if I had five buttons? Six ...?

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Plates of Biscuits

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

Can you rearrange the biscuits on the plates so that the three biscuits on each plate are all different and there is no plate with two biscuits the same as two biscuits on another plate?

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Train Carriages

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

Suppose there is a train with 24 carriages which are going to be put together to make up some new trains. Can you find all the ways that this can be done?

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Octa Space

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

In the planet system of Octa the planets are arranged in the shape of an octahedron. How many different routes could be taken to get from Planet A to Planet Zargon?

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Team Scream

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

Seven friends went to a fun fair with lots of scary rides. They decided to pair up for rides until each friend had ridden once with each of the others. What was the total number rides?

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Bean Bags for Bernard's Bag

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

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?

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Halloween Investigation

Stage: 2 Challenge Level: Challenge Level:1

Ana and Ross looked in a trunk in the attic. They found old cloaks and gowns, hats and masks. How many possible costumes could they make?

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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?

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Chocs, Mints, Jellies

Stage: 2 Challenge Level: Challenge Level:1

In a bowl there are 4 Chocolates, 3 Jellies and 5 Mints. Find a way to share the sweets between the three children so they each get the kind they like. Is there more than one way to do it?

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Calendar Cubes

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

Make a pair of cubes that can be moved to show all the days of the month from the 1st to the 31st.

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Wag Worms

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

When intergalactic Wag Worms are born they look just like a cube. Each year they grow another cube in any direction. Find all the shapes that five-year-old Wag Worms can be.

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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?

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More and More Buckets

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

In this challenge, buckets come in five different sizes. If you choose some buckets, can you investigate the different ways in which they can be filled?

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Buying a Balloon

Stage: 2 Challenge Level: Challenge Level:1

Lolla bought a balloon at the circus. She gave the clown six coins to pay for it. What could Lolla have paid for the balloon?

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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?

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Calcunos

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

If we had 16 light bars which digital numbers could we make? How will you know you've found them all?

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Home City

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

Use the clues to work out which cities Mohamed, Sheng, Tanya and Bharat live in.

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It Figures

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

Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?

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3 Rings

Stage: 2 Challenge Level: Challenge Level:1

If you have three circular objects, you could arrange them so that they are separate, touching, overlapping or inside each other. Can you investigate all the different possibilities?

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Street Party

Stage: 2 Challenge Level: Challenge Level:1

The challenge here is to find as many routes as you can for a fence to go so that this town is divided up into two halves, each with 8 blocks.

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Sealed Solution

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

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?

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Newspapers

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

When newspaper pages get separated at home we have to try to sort them out and get things in the correct order. How many ways can we arrange these pages so that the numbering may be different?

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Three by Three

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

Arrange 3 red, 3 blue and 3 yellow counters into a three-by-three square grid, so that there is only one of each colour in every row and every column

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Rod Measures

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

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?

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Super Value Shapes

Stage: 2 Challenge Level: Challenge Level:1

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?

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Magic Triangle

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

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

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Three Way Mix Up

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

Jack has nine tiles. He put them together to make a square so that two tiles of the same colour were not beside each other. Can you find another way to do it?

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Delia's Routes

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

A little mouse called Delia lives in a hole in the bottom of a tree.....How many days will it be before Delia has to take the same route again?

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Tiles on a Patio

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

How many ways can you find of tiling the square patio, using square tiles of different sizes?

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Plants

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

Three children are going to buy some plants for their birthdays. They will plant them within circular paths. How could they do this?

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Chocoholics

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

George and Jim want to buy a chocolate bar. George needs 2p more and Jim need 50p more to buy it. How much is the chocolate bar?

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Penta Primes

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

Using all ten cards from 0 to 9, rearrange them to make five prime numbers. Can you find any other ways of doing it?

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New House

Stage: 2 Challenge Level: Challenge Level:1

In this investigation, you must try to make houses using cubes. If the base must not spill over 4 squares and you have 7 cubes which stand for 7 rooms, what different designs can you come up with?

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Map Folding

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

Take a rectangle of paper and fold it in half, and half again, to make four smaller rectangles. How many different ways can you fold it up?

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Sweets in a Box

Stage: 2 Challenge Level: Challenge Level:1

How many different shaped boxes can you design for 36 sweets in one layer? Can you arrange the sweets so that no sweets of the same colour are next to each other in any direction?

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Sending Cards

Stage: 2 Challenge Level: Challenge Level:1

This challenge asks you to investigate the total number of cards that would be sent if four children send one to all three others. How many would be sent if there were five children? Six?

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Five Coins

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

Ben has five coins in his pocket. How much money might he have?

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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?

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Waiting for Blast Off

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

10 space travellers are waiting to board their spaceships. There are two rows of seats in the waiting room. Using the rules, where are they all sitting? Can you find all the possible ways?

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Combining Cuisenaire

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

Can you find all the different ways of lining up these Cuisenaire rods?

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Those Tea Cups

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

Place the 16 different combinations of cup/saucer in this 4 by 4 arrangement so that no row or column contains more than one cup or saucer of the same colour.


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