Happy Numbers

Some numbers are happy and others are not!

To find out whether a number is happy, square each of its digits, add the answers and repeat. If you end up with 1 the number is happy!

How many happy numbers can you find?

E.g. Consider 19

12 + 92 = 82
82 + 22 = 68
62 + 82 = 100
12 + 02 + 02 = 1

This shows that 19 is a happy number.

A Mathematics Lesson Starter Of The Day


Share

Topics: Starter | Arithmetic | Investigations

  • C R Walters, Drayton School Oxfordshire
  •  
  • Make it so tht you can flick from day to day while on the page of one particular starter. Also have some way of knowing what date you are on while on a page - in case you want to use a starter from another day
  • Transum,
  •  
  • Good Idea. We have now put navigation links as you suggested at the top of this box. We hope this makes it easier for you to get around. Enjoy the starters,
  • Wikipedia,
  •  
  • In the Doctor Who episode "42", a sequence of happy prime numbers is used as a code for unlocking a sealed door on a spaceship falling into a star, namely 313, 331, 367 and 379.
  • Miss Irons, Blean, Kent
  •  
  • One of my class wants to know if decimal numbers count. 0.1 should be ok but your tester can't cope!
  • Transum,
  •  
  • Sorry Miss Irons. Decimal numbers are not considered to be particularly happy though it was good of your class to be thinking about them. Perhaps your class could come up with a special name for happy decimals?
  • Primary 7, Bargeddie Primary School
  •  
  • Several of our class (Ellie, Thomas, Callum and Nicole) noticed that any numbers made up of 1 followed by any number of zeros e.g. 10, 100, 1000, 10000000, 100000000 etc.! would always be a happy number! :-).

How did you use this starter? Can you suggest how teachers could present or develop this resource? Do you have any comments? It is always useful to receive feedback and helps make this free resource even more useful for Maths teachers anywhere in the world.
Click here to enter your comments.

If you don't have the time to provide feedback we'd really appreciate it if you could give this page a score! We are constantly improving and adding to these starters so it would be really helpful to know which ones are most useful. Simply click on a button below:

Excellent, I would like to see more like this
Good, achieved the results I required
Satisfactory
Didn't really capture the interest of the students
Not for me! I wouldn't use this type of activity.

This starter has scored a mean of 3.3 out of 5 based on 324 votes.


Previous Day | This starter is for 25 January | Next Day

 

Answers



Your access to the majority of the Transum resources continues to be free but you can help support the continued growth of the website by doing your Amazon shopping using the links on this page. Below is an Amazon search box and some items chosen and recommended by Transum Mathematics to get you started.

Have you read Craig's book yet?

Craig Barton must surely be the voice of Mathematics teachers in the UK. His wonderful podcasts interviewing the industry experts have culminated in this wonderful book. As Craig says: "I genuinely believe I have never taught mathematics better, and my students have never learned more. I just wish I had known all of this twelve years ago..." more...

"How I wish I’d taught maths' is an extraordinary and important book. Part guide to research, part memoir, part survival handbook, it’s a wonderfully accessible guide to the latest research on teaching mathematics, presented in a disarmingly honest and readable way. I know of no other book that presents as much usable research evidence on the dos and don’ts of mathematics teaching in such a clear and practical way. No matter how long you have been doing it, if you teach mathematics—from primary school to university—this book is for you." Dylan Wiliam, Emeritus Professor of Educational Assessment, UCL.

The Craig Barton Book

Casio Classwiz Calculator

There is currently a lot of talk about this new calculator being the best in its price range for use in the Maths classroom. The new ClassWiz features a high-resolution display making it easier to view numerical formulas and symbols but it isn't a graphical calculator as such (it has the capacity to draw graphs on your smart phone or tablet, via a scannable QR code and an app).

As well as basic spreadsheet mode and an equation solving feature you also get the ability to solve quadratic, cubic or quartic polynomial inequalities and the answer is given just as it should be written down, using the correct inequality symbols!

This calculator has a high-performance processor and twice the memory of previous models ensuring speedy operation and superior computational power.more...

Texas Instruments Nspire 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 gift for a special occasion 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 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 gift you could add a link to iPad Maths to the home screen.

Click the images above to see all the details of these items 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.

Transum.org/go/?Start=January25

Here is the URL which will take them to an interactive Happy Numbers activity.

Transum.org/go/?to=Happy

Student Activity

 


Apple

©1997-2018 WWW.TRANSUM.ORG