In the northern hemisphere it’s summer time and here in the UK we are in the middle of an uncharacteristic hot spell. The back garden has become an extension to the house and I am typing this sitting on a plastic chair at a plastic table. The Maths that I think of as I look at the garden is the mathematics of nature. I see **Fibonacci numbers** in the petals and spirals and remember the great time in the past when pupils have enjoyed the great outdoors doing the **Scavenger Hunt** and **People Maths**. This activity suggestion comes with a sun screen and hydration warning!

As I have done a lot of travelling in June there have not been as many new additions to the website as during a typical month but I can tell you about **Recipe Ratios**, a series of short exercises based on recipes for Thai dishes. They complement the other ratio exercises on the website and come complete with the full method in case you fancied cooking the delicious Siamese food.

**Bottles, Boxes and Cans** is an activity with two levels. Level one is a drag and drop challenge to match the photograph of a container with its capacity. Level two is a little harder, a more traditional exercise on volume and capacity.

The puzzle of the month is actually the new Starter of The Day for June 12^{th}. It is called **Weather Report** and puts the puzzle in the context of mean temperatures. The answer is -1, 1, -2, 2, 3.

If this was too easy for you (or your students) there is an extension provided as a new **Advanced Starter**. What other products of five numbers (less than 100) would have given unique solutions? The answer to that is at the bottom of the **Weather Reports** page.

I’m off to visit Bletchley Park on Tuesday to see the location of the top-secret codebreaking operation during the Second World War. There is a great amount of mathematics involved in deciphering messages as can be seen in the **Code Cracking** presentation. I’m sure I’ll have more to say on the topic in next month’s newsletter.

That’s all for now,

John

P.S. Calendars, their days are numbered.

]]>Imagine a 10cm by 15cm rectangle. What is the largest square that can be drawn snuggly in one corner that just touches the rectangle’s diagonal. The answer will be at the end of this newsletter.

Now let’s dive into the new activities added to the Transum website this last month.

The Value of Places is, as the title suggests, a place value quiz. It can be sometimes difficult to find more challenging place value activities for Secondary students as they have been learning about place value since early Primary and have probably done the usual types of activity. This online exercise challenges pupils to figure out how many times bigger the value represented by one digit is than the value of another digit in the same number.

Prime Pairs Game is for two players who take it in turns to add a numbered card to either end of a row of cards so that every adjacent pair of cards adds up to a prime number.

Graph Paper has been updated. I think it is the quickest way you can print a sheet of graph paper with numbered axes to suit any graph you may need to draw.

eQuation Generator has also been updated. Its only function is to present you, the teacher, with an endless supply of linear equations that you can project in front of your class. The update improves the delicate balance between providing more of the same while presenting many variations of the chosen type of equation.

Likelihood is a new title given to the probability sorting activity. A pupil’s ordering of the given situations is matched against the average ranking of all the other people who have done the activity.

Loci Land is live but not yet finished at the time of writing this newsletter. I do expect it to be completed in the next week. It currently contains two real life situations that pupils copy on to squared paper then draw the constructions in order to answer the loci question. More questions will be added soon.

I heard an interesting fact on a podcast I subscribe to last month. Did you know that rather than (in the UK) having 1p, 2p, 5p etc. coins it would be mathematically more efficient to have 1p, 3p, 11p and 37p coins? I have included the excerpt from the podcast in the Transum podcast for this month which you can find at Transum.org/Podcast. If anyone would like to share a proof of that in a form that pupils could understand please let me know and if facts like that are your thing, don’t miss the Maths Trivia page.

On a different subject I am happy to say that you now have the option of viewing Transum webpages via https: as well as http:. This development took place last month when the more secure protocol was implemented. SSL (Secure Sockets Layer) is the standard security technology for establishing an encrypted link between a web server and a browser. This link ensures that all data passed between the web server and browsers remain private and integral. SSL is an industry standard and is used by millions of websites around the world.

Finally the answer to this month’s puzzle is that the area of the biggest square would be 36 square centimetres. You can see the diagram and my method on the ‘Square in Rectangle’ Advanced Starter page.

That’s all for this month,

John

P.S. If a got 50 pence for every time I failed a maths exam I’d have about £6.30 now

]]>The puzzle for this month was inspired by the recent London marathon. Sue Watserface runs the first half at an average speed of 5 miles per hour. What speed would she have to run the second half of the course to attain average speed of 10 miles per hour for the whole race? (answer at end of this newsletter)

The new addition to the website in April that I am most excited about is the Transum version of The Royal Game of UR.

My version is called Remainder Race. Players have to get seven counters around the traditionally shaped board and the number of hops they can make is determined by the remainder left when the number of the square their counter is on is divided by the chosen dice number. In addition to the numeracy skills required there are strategies to be discovered and excitement all round.

It is a game for two players or one player playing against the computer. I am keen to hear how well it works with your pupils. Please let me know.

After writing half of the code for the game on a long-haul plane journey into London, I made it my mission to visit the British Museum and photograph one of the two original game boards. They date from the First Dynasty of Ur, before 2600 BC, thus making the Royal Game of Ur one of the oldest examples of board gaming equipment ever found.

Filling a gap in Transum’s English National Curriculum coverage an online exercise called Furthermore has been created which provides practice for the skill of counting forwards or backwards in steps of powers of ten for any given number up to a million.

Nine Digits is an addition puzzle presented in eight levels of increasing difficulty. You can drag and drop the digits into place. At the time of writing already 78 trophies have been earned for completing the puzzle but no one has yet succeeded beyond level six.

Another new puzzle is called Cubical Net Challenge. Your mission is to paint the faces of the ten cubes represented by their nets. You have two colours, blue and red. No two cubes should look the same no matter which way round the cubes are turned.

Hexblock Hunter is an online game is inspired by TV’s Blockbuster programme (are you old enough to remember that?) and targets lower Secondary/High school mathematical vocabulary. It works best with two players or two teams but the rules can be adapted to create an individual learning activity.

Finally the Privacy Policy has been up dated to specifically address the key features of the new European General Data Protection Regulation (GDPR) legislation which comes into effect later this month.

And now the answer to this month’s puzzle. I was lucky enough to be in London at the time of the marathon. The weather was great for the spectators but a little too hot for the runners.

The length of the London marathon is 26.2 miles but you didn’t need to know that to answer this question. The fact is that the time it would take to run any distance averaging 10mph would have been completely used up by running half that distance at 5mph so only an infinite second half speed would suffice!

Thanks to all those of you who provide feedback, suggestions and ideas for the Transum website. Your messages are very much appreciated.

That’s all for this month.

John

P.S. I don’t trust people with graph paper. They’re always plotting something!

]]>First on the agenda is the puzzle of the month.

Aynuk and Ayli needed to cut the grass of their square lawn. They agreed that each person should cut half of the area of the square. Aynuk went first and cut a one metre wide border all the way around the lawn. Ayli then cuts the rest of the grass. What was the length of the sides of the lawn?

While you think about that (the answer is at the end of this newsletter) here are the most significant activities that have been added to the Transum website this last month.

Pie Charts. Pupils can practise the skills to construct and interpret pie charts using this self-marking set of exercises. Don’t forget that you, as a subscriber, can keep track of the trophies earned by your pupils in the Class Admin section of the website.

Pie Chart Creator. This is a quick and convenient tool for rapidly creating simple pie charts. It came about as a result of me needing to create pie charts for the activity mentioned above. It doesn’t have lots of features but its strength is its ease of use for fast results.

Pick up Sticks. If you were to pick up the sticks from the pile (randomly generated when the page loads) so that you were always removing the top stick what calculation would you create? What would be the answer to that calculation? This can be used as part of your BIDMAS (PEMDAS) revision repertoire.

Snow days Maths. Some mathematical activities to keep pupils’ brains active and continue their learning while school is closed due to bad weather (or any other reason). Links are provided towards the bottom of the page which you can send to your pupils so they can access the particular activity set you have chosen.

Emergency Maths lessons. An ever-growing collection of mathematics lesson plans to be used on the rare occasions when a class is left without their normal teacher and you are stepping in at very short notice. I’m guessing most people won’t use them in full but cherry pick the good ideas!

Online Logo Levels 2 and 3. What is now level 1 of online logo has been an extremely popular part of the Transum website for some time. The two new levels use a more sophisticated version of the Logo programming language with many more commands available. The challenges in Level 2 include using bearings to guide the turtle and Level 3 introduces procedures.

Graph Equation Pairs. A collection of activities and games involving matching the equation with the image of its graph. The graphs include quadratics, cubics, reciprocals, exponential and the sine function. Good for a lesson Starter or Finisher.

Simultaneous Solutions. Arrange the given pairs of simultaneous equations in groups to show whether they have no solution, one solution or infinite solutions.

Ratio Clues. Arrange the ratio clues in the clouds in a logical order to work out the values of the twelve letters. Involves simplifying ratios and recognising equivalent ratios.

Last month I told you about the new activity called Olympic Rings. There are three levels each with a different ring total. These are 11, 13 and 14. One teacher asked why there was not a level based on a ring total of 12. Apparently it can’t be done but how do you prove it?

I had a go at proving it but got stuck. I even resorted to posing the question on Reddit and although a computer programmer proved it using a brute force (the exhaustion method), I am sure there must be a short, elegant proof out there somewhere. So if you can prove the ring total cannot be 12 please share your proof.

For future reference there are two ‘mirror’ sites that contain all the Transum Starters and activities. They are at www.transum.com and www.transum.info The only difference is that they don’t contain the details of your Transum subscription account so you won’t be able to log in there. If it looks like Transum.org will be offline for a long time then I will transfer the database containing your details to Transum.com so you will eventually be able to log in there too. Fingers crossed that there are no hosting issues in the pipeline.

Newsletter puzzle answer: Let the sides of the inner square that Ayli cuts be x metres long. The sides of the square of the whole lawn will therefore be x+2 metres long.

As the whole lawn has twice the area of the inner square the following equation can be constructed:

2x^{2} = (x+2)^{2}

2x^{2} = x^{2} + 4x + 4

x^{2} – 4x – 4 = 0

This can be solved using the quadratic formula and the positive solution gives the practical value of x

The answer (length of the sides of the lawn) is 6.83m (to 3 sf)

That’s all for now. Have a good April

P.S. There’s a fine line between numerator and denominator!

]]>Three people enjoyed a meal at a restaurant. The waiter brings the bill for £30 so each person pays £10. Later the chef realises that the bill should have only been £25 so he sends the waiter back to the table with five pound coins. The waiter could not figure out how to divide the £5 so he gave each person a £1 and kept £2 for himself.

So….the three people have paid nine pounds each for the meal: 3 x £9 = £27

The waiter kept two pounds: £27 + £2 = £29

What happened to the other pound?

The new answer will be at the bottom of this newsletter but before that here are some of the new resources added to the website this last month.

Go Figure is a number placing puzzle in which interconnected addition, subtraction. multiplication and division calculations have to be completed using the digits one to nine.

I got quite excited when I saw pupils using this activity for the first time and heard them talk about their insights. The puzzle can be used to introduce a new problem-solving strategy for this kind of task. Rather than concentrate on which digits could go in the available spaces, make a list of the digits that could not possibly go into the spaces. You really need to try this yourself to see how the properties of the four rules are analysed in the puzzle solving thinking. Make sure you click the ‘Show Tags’ button to assist you find the solution.

Olympic Rings was put together to coincide with the Winter Olympics but the relevance of the puzzle will live on during this inter-Olympic time. There are three levels of difficulty with the lower levels being made easier with some pre-placed digits. This makes the puzzle accessible to younger children but also provides a starting point for an advanced level proof investigation.

Map Scales came about because, after being asked for a good exercise on ratios as used in map scales, I couldn’t find one! There are two levels and the second level introduces the tricky and not necessarily intuitive notion of area scale factors.

Barmy BIDMAS Is a new advanced Lesson Starter. You will need to know about the order of operations and factorial notation to appreciate the subtly of this mathematical wonder. Students could be challenged to make a similar calculation with the surprising value of 6!

Time Sort is the latest additions to the ‘Telling the Time’ collection. There are three levels including digital times, analogue clocks and phrases to represent times. Try using it with pupils working in pairs and listen to the discussion generated.

Sum to One is a set of decimal numbers on virtual cards which can be used for a matching activity. A pairs game, a multiple choice quiz, a tug-of-war game and a snap game. Is that too much choice?

The book I am reading at the moment is Craig Barton’s new book How I Wish I’d Taught Maths: Lessons learned from research, conversations with experts, and 12 years of mistakes. I am a great fan of Craig’s podcasts (I listen to them on my Tuesday morning cycle ride) and this book collects together the insights Craig has collected from all of the educational experts he has interviewed. At the time of writing, 93% of the reviewers on Amazon had awarded the book five out of five stars. I thoroughly recommend this book to you here.

Thanks to those of you who have posted photographs on Twitter of the Transum activities being used in the classroom. It is so good to see that the work that went in to producing the resources was worthwhile. Thanks

If you follow me on Twitter (@Transum) you may have noticed that my list of ‘Hidden Gems on the Transum Website’ has been growing from the 19 included in the last newsletter. I think I will stop when I get to 50.

Now let’s continue the search for the missing pound from the puzzle of the month. One hour later two elderly ladies came into the restaurant and enjoyed a meal together. The waiter brings the bill for £30 so each lady pays £15. The chef again tells the waiter that the bill should have only been £25 so he sends the waiter back to the table with five pound coins. The waiter could not figure out how to divide the £5 so he gave each lady a £1 and kept £3 for himself.

So….the two ladies have paid fourteen pounds each for the meal: 2 x £14 = £28

The waiter kept three pounds: £28 + £3 = £31

So there is the missing pound! Genius isn’t it? I heard this solution on the Danny Baker radio show and have included the audio excerpt towards the bottom of the June 19th Starter of the Day. It’s worth listening to. Enjoy.

All the best for the month ahead

John

P.S. Always wear glasses to Maths lessons. They help with division!

]]>“Divide 45 in four parts, so that the first part with two added, the second with two subtracted, the third divided by two, the fourth multiplied by two, shall be equal to each other.”

That will give you something to think about. It’s not a familiar puzzle format is it? The answer can be found at the end of this newsletter.

The three most noteworthy new learning objects added to the Transum website this last month are as follows:

Frequency Trees: Being able to construct and read these diagrams is a new topic which appears on both the higher and foundation GCSE(9-1) specifications. This interactive exercise requires pupils to fill in the partially completed frequency trees then try some exam-style questions that introduce calculating probability from the numbers in the trees.

Number Grids: I have started collecting a variety of activities that can be enjoyed using this page of customizable number grids. As a Transum subscriber you get access to buttons that can quickly colour in the grids with the most common number patterns for pupils to describe. Please let me know if you have other ideas for number grid learning activities.

Old Equations: Most students can deepen their mastery of linear equation solving with these old, but just as good as new, intelligently varied questions. These linear equations appeared in a book called A Graduated Series of Exercises in Elementary Algebra by Rev George Farncomb Wright published in 1857.

The book I’m reading at the moment is “What does this look like in the classroom?: Bridging the gap between research and practice” by Carl Hendrick and Robin Macpherson. It is a very readable book in which the current educational experts answer the commonly asked questions about learning backed by the latest research. You can dip in and out of the book focusing on the chapters that interest you. The chapter headings are: Assessment, Marking and Feedback, Behaviour, Reading and Literacy, Special Educational Needs, Motivation, Memory and Recall, Classroom Talk and Questioning, Learning Myths, Technology and Independent Learning.

The thought buzzing around my mind at the moment is the notion that “I think the paradox is that the things that make you a good independent learner don’t necessarily look like independent learning.” Or in other words “…independent learning might be a desired outcome, but paradoxically, it may not be the best way to achieve that outcome.” Get a copy of the book and read about this and other Maths teacher dilemmas.

Over the last couple of weeks I have been posting “Hidden gems on the Transum website” on Twitter. The idea is to make teachers aware of some of the Transum pages I think are really useful but you wouldn’t necessarily think of searching for. They are also like needles in a haystack as there are over 4000 pages indexed by Google on the Transum website. Here are the gems I’ve already tweeted at the time of writing.

1: Triangle Solver

2: Mix and Math

3: Mind Reader

4: Refreshing Revision

5: Pong Hau

6: Old Equations

7: Graph Patterns

8: Box Plots

9: Venn Paint

10: Heptaphobia

11: Great Expectation

12: Number Grids

13: Transformations

14: Sheep Herding

15: Systematic Listing

16: Areas Investigation

17: Number Line

18: Exam-Style Questions

19: Area Wall Puzzles

More will be tweeted soon as there are many more hidden gems. You can find out about them if you follow me (@Transum) on Twitter.

The answer to the puzzle of the month is 8, 12, 20 and 5

That’s all for this month,

John

P.S. What do you need to calculate the distance around a circle of sheep?

Answer: Shepherds’ Pi.

]]>This month’s puzzle is taken from the excellent book I have been reading during the holiday called “Can You Solve My Problems” by Alex Bellos. I have just read the problem called “The Shrivelled Spuds” which I present to you here:

A pile of potatoes weighing 100kg is put in the sun. Ninety nine per cent of the weight of the potatoes is made up of water. After a day some of the water evaporates., with the result that 98 per cent of the weight of the potatoes is now made up of water. What’s the new weight of the potatoes?

The answer is at the end of this newsletter.

I thoroughly recommend the book as not only is it an ordered collection of intriguing puzzles but it also has an extensive solution section in which Alex provides insights, history and worked solutions for the puzzles. The chapters are Logic Problems, Geometry Problems, Practical Problems, Problems with Props and Problems for Purists. Here is a link to buy the book from Amazon.

Last month the website was added to and updated as usual but the one new activity I would like draw your attention to is the Area Wall Puzzles. The core concept is a puzzle called Shikaku, an original Nikoli puzzle and though the Transum version refers to area, the activity requires the ability to consider factor pairs of small numbers.

In the process of creating and testing the puzzles I realised how addictive this type of problem solving is. Just like Sudoku solving you will develop strategies as you become more proficient and experience a nice sense of accomplishment when the wall is completely coloured in.

Another new activity is called “Equation of a Line Through Points“. It is a four level exercise requiring users to match the equations of the straight line graphs to the clues about gradients and points. This exercise could be attempted after some of the more basic “y=mx+c” activities have been mastered.

Finally, my answer to this month’s puzzle is 50kg

I found this by first realising that if 99% of the original pile is water then 1% must be other, dry matter.

1% of 100kg is 1kg.

Let the weight of the potatoes after the drying be *x*.

0.98*x* + 1 = *x*

1 = 0.02*x*

*x*= 50

That’s all for now

John

P.S. You have to be odd if you want to be Number One.

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Young Noel Stocking checked his bank account to see how much money he had to buy Christmas presents. When he recorded the balance he wrote down the number of pence for pounds and the number of pounds for pence. A transposition error. “Wahoo” he exclaimed “I’m rich!”

While in this good mood Noel promised 50p to his younger sister Merry. He adjusted his record accordingly which now turns out to be exactly double the amount in the bank.

How much does Noel have in the bank?

Many of the activities on the website have been updated during November and, in preparation for the festive season, the Christmaths collection has been brightly polished. Here are my favourites:

Christmas Ornaments: A puzzle which can be solved online or by using the printable boards so the task can be done in a very practical way with real Christmas ornaments. Problem solving, trial and improvement and logic all wrapped up in one for Christmas.

Christmas Eve Snow: This is a letters-replace-digits puzzle which comes with clues and, if you scroll down to the bottom of the page, a step-by-step guide for solving this kind of puzzle.

Christmas Tables: This is the special Starter for Christmas Day. When I first saw the Betty Edwards drawing I was amazed that the sense of perspective is so powerful. You will need Flash to view the animation.

Cracker Joke: This is a basic numeracy activity where answers to simple calculations are converted to letters to spell out a maths joke. Each time the page loads the calculations change. You can change the joke too.

The Power of Christmas: This Starter works well with Year 11 and Year 12 pupils as it tests their understanding of indices. Finding one solution is fine but the real challenge is to find all four solutions.

The Twelve Days of Christmas: This is a well-worn and time-honoured problem that’s certainly doesn’t deteriorate with age. I particularly like the solution as sung by Natalie Cole.

Christmas Tree Trim: This is just one of the activities on the Transum website that allows pupils to demonstrate their systematic listing skills. There are eight levels of difficulty and a trophy available for each level.

The links to all of these activities (and more) can be found on the Christmaths page. The last week of term is a great time to do some out-of-the-ordinary mathematics with your pupils and there are plenty of ideas on that page. In my experience some of the end-of-term, fun maths has turned out to be the most memorable and enjoyable learning my pupils did all year!

Have your pupils encountered the binary system? There is a visual aid you can use called Binary Lights to demonstrate how binary works. The reason I mention this is that recently I heard a nice idea about counting on your fingers. It’s common knowledge that you can count to ten with the help of fingers and thumbs but if you use binary you can count up to over 1000! Scroll down the Binary Lights page to see a video demonstration.

The answer to this month’s puzzle is £16.33. I found this answer with the aid of a spreadsheet. Please let me know if you have another way of finding this answer.

That’s all for this month

Enjoy the holiday

John

Q. How is an artificial Christmas tree like the square root of minus nine?

A: Neither has real roots!

]]>The puzzle for this month is about Percy Cod and Patsy Eal who are both shepherds. They keep sheep in adjacent fields near the source of the river mint. Can you work out how many sheep each person owns from the following clues?

- If Percy sold seven sheep to Patsy, both shepherds would have the same number of sheep.
- If Patsy sold seven sheep to Percy then Percy would have exactly twice as many sheep as Patsy.

The answer can be found at the end of this newsletter.

Talking of sheep, I would like to recommend the Transum podcast for this month. It has a strong sheep counting theme. Within the podcast there are excerpts from the ‘No Such Thing as a Fish’ podcast and the Chris Evans Radio 2 breakfast show, both discussing the skill of counting sheep.

If you haven’t yet found them there are three sheep related activities on the Transum website: Estimating Sheep is designed to develop your count estimating skills, Herding Sheep introduces Loci and Coloured Sheep is a quick Maths Lesson Starter involving probability.

If all this sheep counting hasn’t sent you to sleep you might still have the energy to explore the seven new additions to the Transum website last month:

- Angle Chase – Find all of the angles on the geometrical diagrams. Knowledge of basic angle theorems (in a triangle, on a line and between parallel lines) is required.
- Snake Sort – Sort the coloured snakes in a logical order. This activity introduces systematic listing.
- Indices True False – Arrange the given statements involving indices to show whether they are true or false. A knowledge of the laws of indices is required.
- Yes No Questions – A game to determine the mathematical item by asking questions that can only be answered yes or no. Includes shapes graphs and mathematical words.
- Combinations and Permutations – Learn how to tell the difference between permutations and combinations and use the formulae to answer questions.
- Identity, Equation or Formula? – Arrange the given statements in groups to show whether they are identities, equations or formulae.
- Birthday Card – A mathematical birthday card which prints on A4 card (double sided). Believe it or not this birthday card also has a sheep counting theme!

Thanks to Felton Davis for sharing his “work of a lifetime” on the Pentominoes page. Felton has created an algorithm to create 2339 solutions which are linked to from the bottom of the pentominoes page.

Thanks also to Christopher Allan who has suggested the following extension to the “A Number” Starter: “When written as a word or words, the smallest positive whole number containing the letter ‘a’ is one hundred and one after which they all contain ‘a’ up to X (but what is X ?).”

The answer to this month’s sheep-owning puzzle can be found by setting up two simultaneous equations. Let the number of sheep owned by Percy be x and the number of sheep owned by Patsy be y.

Did you also conclude that Percy has 49 sheep and Patsy has 35 sheep?

That’s all for now,

John

P.S. f(x) walks into a bar. The barman says, ‘Sorry, we don’t cater for functions!’

]]>In the fantasy world of Maths puzzles there aren’t any stopwatches but there are two egg timers. One of them measures 7 minutes and the other measures 4 minutes. I want to use them to time my daily juggling practice which I want to last for exactly 9 minutes. How can I do it?

The answer, if you don’t manage to figure it out yourself, is at the end of this newsletter.

The most amazing thing I learnt this month was the effect the number seven has on exam performance. I have been teaching since the early eighties and didn’t, until this month, know about this surprising phenomenon.

The news came to me via the wonderful Mr Barton Podcast. Craig was interviewing Trevor Senior who is AQA’s Chief Examiner for the Maths GCSE. When asked about his favourite number seven he related the astonishing fact that if the number seven appears in an exam question the success rate drops by about 10%.

I was fascinated by this and it gave me an idea for a Transum activity that would collect some data. I decided on a ten question exercise intended to test pupils’ written methods. The add, subtract, multiply and divide questions would be randomly generated in pairs. One question of the pair would contain a seven and the other would not. Pupils type in their answers and the system would mark them. The data from those getting at least five questions correct would be recorded in the database and then presented to the pupils at the end of the exercise.

It is intended that pupils do the exercise without knowing the purpose of the data collection. The exercise is a good opportunity to practise written methods so that can be given as the reason for doing it. The title ‘Heptaphobia Research’ is suitably cryptic to disguise the data-collection purpose of the exercise.

At the time of writing only ten people have completed the exercise and the results show that the number seven does not have the effect I was expecting but it’s early days. We need hundreds of people to contribute to the data before we can begin confirming our hypothesis.

With that in mind could I ask that if you have a class that could do with a bit of arithmetic practice, **please ask them to do this activity**. The more people that take part, the more valuable the data will be. It would be good if the database grows to be the same size as the times tables database which currently has over two hundred thousand sets of data.

An activity that has been on the Transum website for many years now is called Pentransum. It is a collection of multiple choice questions suitable for pupils in Key Stage 3. When a pupils has answered 20 questions correctly they are invited to suggest a question of their own. If I consider it to be suitable it is added to the collection of questions in the database.

When designing a good multiple choice question, as well as coming up with meaningful distractors, you have to choose in which position the correct answer will appear. I found it interesting that about twice as many submissions placed the correct answer in the middle position (C) than the two extreme positions (A) or (E). I guess that’s human nature to subconsciously think that something in the middle is more hidden than something on the outside.

I have used a Casio fx350ms calculator with GCSE students for many years but, to keep up with developments, have now got a Casio fx350es plus. I’m sure many people, like me, don’t have the time to learn all the functions available and sometimes a student will show you something that will stop you in your tracks. Last month I learned that the FACT function will display a number in its prime factors. Very useful for working out if a large number is prime.

One of the new additions to the website last month is a multi-level quiz called Systematic Listing Strategies. Level 1 is a collection of listing puzzles for younger children which encourage them to develop logical methods of listing. The higher levels include standard combination and permutation questions. Let me know what you think.

Here is the answer to this month’s puzzle. Start the seven and four minute egg timers together. As soon as the four-minute timer has finished start it again.

When the seven-minute timer has finished start juggling.

Restart the four-minute timer two more times each time it finishes to obtain the nine minutes of juggling time.

That’s all for this month.

Don’t miss the 31^{st} October Halloween Starter!

John

P.S. Why do mathematicians think that Halloween is the same as Christmas?

Answer: 31 Oct = 25 Dec

[Think number bases!]

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