Upside Number

Fonia noticed that her phone number read the same when viewed upside down.

Her number began 081 and was followed by seven digits.


The two digit number formed by the fifth and sixth digits is divisible by eleven.

The two digit number formed by the fourth and fifth digits is divisible by nine.

The two digit number formed by the sixth and seventh digits is a square number.

What is Fonia's phone number?

Updide Number

A Mathematics Lesson Starter Of The Day


Topics: Starter | Number | Puzzles

  • Sue Mainstone, Sir Charles Lucas arts college
  • Should have said todays number was planindromic as well
  • Micky Bullock, Harrogate
  • Another solution is 0816336180.
  • Miss Gilleece, Boldon School
  • My 9A1 got the answer in 3.2 minutes, Chris was the first to come up with the correct answer.......which is quite amazing considering!!!
  • Mrh, Neb
  • I had a student had completed this in less than two minutes! Can anyone beat that!
  • Jay, Yeates
  • Micky, your answer is wrong as it isn't the same when read upside down.
  • Cheryl Joinson, Sychdyn School
  • I'm using starter of the day every mornign in my primary class.
    Our answer was 0811881180 but we have no way of checking if we are correct.
  • Geraint White, Hadleigh High School
  • I got 0819116180.
  • Fran,
  • Another soloution is 0816699180.
  • Cheryl, Sychdyn Primary School
  • Geraint & Fran sorry but both your answers are wrong - the corect answer is at the bottom of this page - and my primary school class got it right! :-).
  • Sally S, Barham School
  • Love reading the comments - sometimes V competitive between teachers themselves;).
  • Mr. Dean, Varee International
  • What about 0810000180?
  • 5DC, Lee On The Solent Junior School
  • We think the answer is 0811881180 :).
  • Top Group Y5, ST JOHN'S SCHOOL
  • The boys loved this.
  • Mr P Darch, FMS - Tom, Luke And Lucy
  • Enjoyed this and my Year 6 class solved in about 4 minutes.
    By the way the only answer is 0811881180 - the others either do not look the same upside down or do not satisfy the other rules.
  • Mr Staples, Otamatea High School
  • My students enjoyed this and some found it quite easy Two boys completed in 2 minutes.

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Can you make up some clues for your own phone number?

Christmas Present Ideas

It is often very difficult choosing Christmas presents for family and friends but so here are some seasonal, mathematics-related gifts chosen and recommended by Transum Mathematics.

Equate board game

Here's a great board game that will give any family with school-aged kids hours of worthwhile fun. Christmas is a time for board games but this one will still be useful at any time of year. Games can be adapted to suit many levels of Mathematical ability.

For Maths tutors working with just one or small groups of pupils this game has proved to be an excellent activity for a tutorial. Deciding on the best moves can spark pertinent discussions about mathematical concepts.

Equate looks a bit like Scrabble--for aspiring mathematicians, that is. Designed by a real mathematician, it works like this: You put down tiles on a board and make points by correctly completing simple equations. Your nine tiles include both numbers and mathematical symbols; you can add on to previous plays both vertically and horizontally. more...

How Not To Be Wrong

The maths we learn in school can seem like an abstract set of rules, laid down by the ancients and not to be questioned. In fact, Jordan Ellenberg shows us, maths touches on everything we do, and a little mathematical knowledge reveals the hidden structures that lie beneath the world's messy and chaotic surface. In How Not to be Wrong, Ellenberg explores the mathematician's method of analyzing life, from the everyday to the cosmic, showing us which numbers to defend, which ones to ignore, and when to change the equation entirely. Along the way, he explains calculus in a single page, describes Gödel's theorem using only one-syllable words, and reveals how early you actually need to get to the airport.

What more could the inquisitive adult want for Christmas? This book makes a cosy, interesting read in front of the fire on those cold winter evenings. more...

Graphic Display Calculator

This handheld device and companion software are designed to generate opportunities for classroom exploration and to promote greater understanding of core concepts in the mathematics and science classroom. TI-Nspire technology has been developed through sound classroom research which shows that "linked multiple representation are crucial in development of conceptual understanding and it is feasible only through use of a technology such as TI-Nspire, which provides simultaneous, dynamically linked representations of graphs, equations, data, and verbal explanations, such that a change in one representation is immediately reflected in the others.

For the young people in your life it is a great investment. Bought as a Christmas present but useful for many years to come as the young person turns into an A-level candidate then works their way through university. more...

iPad Air

The analytics show that more and more people are accessing Transum Mathematics via an iPad as it is so portable and responsive. The iPad has so many other uses in addition to solving Transum's puzzles and challenges and it would make an excellent Christmas gift for anyone.

You have to hold iPad Air to believe it. It’s just 7.5 millimeters thin and weighs just one pound. The stunning Retina display sits inside thinner bezels, so all you see is your content. And an incredible amount of power lies inside the sleek enclosure. So you can do so much more. With so much less. more...

Before giving an iPad as a Christmas gift you could add a link to iPad Maths to the home screen.

Aristotle's Number Puzzle

It’s a bit of a tradition to give puzzles as Christmas Gifts to nieces and nephews. This puzzle is ideal for the keen puzzle solver who would like a challenge that will continue over the festive period (at least!).

This number puzzle involves nineteen numbers arranged into a hexagon. The goal of the puzzle is to rearrange the numbers so each of the fifteen rows add up to 38. It comes in a wooden style with an antique, aged look.

Keep the Maths in Christmaths with this reasonably priced stocking filler. more...

The Story Of Maths [DVD]

The films in this ambitious series offer clear, accessible explanations of important mathematical ideas but are also packed with engaging anecdotes, fascinating biographical details, and pivotal episodes in the lives of the great mathematicians. Engaging, enlightening and entertaining, the series gives viewers new and often surprising insights into the central importance of mathematics, establishing this discipline to be one of humanity s greatest cultural achievements. This DVD contains all four programmes from the BBC series.

Marcus du Sautoy's wonderful programmes make a perfect Christmas gift more...

Click the images above to see all the details of these gift ideas and to buy them online.

Online Maths Shop

Laptops In Lessons

Teacher, do your students have access to computers?
Do they have iPads or Laptops in Lessons?

Whether your students each have a TabletPC, a Surface or a Mac, this activity lends itself to eLearning (Engaged Learning).

Laptops In Lessons

Here a concise URL for a version of this page without the comments.

Here is the URL which will take them to a related student activity.

Student Activity


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