If you live in the northern hemisphere you are probably starting a new school year so happy new year to you. Wherever you live you are welcome to the Transum Mathematics newsletter for September 2016. As usual I will begin with the puzzle for this month which is called Separated Twins.

The twins have a safe. The combination of the safe is a six digit number.

Within this six digit number there are two ones separated by one other digit. There are two twos separated by two other digits and there are two threes separated by three other digits.

What is the combination?

As there was no August newsletter there are two months’ worth of new content on the Transum website to tell you about. Let’s begin with the Mathematical Optical Illusions.

This has proved to be a useful visual aid to use while revising some basic geometrical facts with pupils. The illusion bit provides the motivation to study the diagram while you, as the teacher, can sneak in the revision questions such as ‘what is formula for the area of a circle?’, ‘What does arc mean?’ and ‘Name four different types of triangle’. I’m sure you could come up with suitably challenging questions for your pupils as you work your way through the different illusions.

Most Transum subscribers are Secondary/High School teachers but there is a significant proportion of primary teachers too.

This next item is only really relevant to Secondary teachers preparing pupils for GCSE or IGCSE exams. In the UK, next May sees the first of the new style 9 to 1 grade GCSE exams. The Transum think tank has studied the sample assessment materials produced by the exam boards and come up with similar practice questions along with fully worked solutions. These questions have been collected together into 20 practice papers which print nicely onto A4, double sided paper.

One Minute Maths is a hoot! So funny to see good mathematicians making the classic mistake. It’s a bit of fun but highlights a valuable place value, carrying issue. Give it a try (when no one is looking).

Puzzle Cube is a multi-level challenge based on the idea of a Rubik’s-style cube presented as a net. At the time of writing only one person has managed to earn a trophy for the hardest level.

Pupils in general always need more practice with basic mental arithmetic so the more different activities you have to provide that practice the better. Here’s a new two player game for your collection. It’s called Tug of War and has levels for each of the four rules. It can also be played with any of the many Pairs games on the Transum website. Scroll down the Tug of War page to see the links.

You probably already know that there are a range of times tables activities available on the Transum website but Hard Times is new. It is nothing to do with the Charles Dickens novel but is so named as it isolates the hardest times tables facts according the data collected from over ninety thousand trials as can be seen on the Statistics page.

The Calculator Workout page is a visual aid which demonstrates key skills with a common scientific calculator.

The latest pairs game is about Circle Angle Theorems. Not a substitute for practice answering questions and solving problems but a fun support activity.

I hope you enjoy the new activities on Transum.org. Don’t forget that if the website should ever go offline (let’s hope not) you can still get to your favourite activity by using one of the two mirror sites Transum.info and Transum.com. Currently you cannot log in as a subscriber on the mirror sites but if the main site looks as though it will be down for a long time that will change.

The answer to this month’s puzzle is 3 1 2 1 3 2 (or that number with the digits reversed). If you thought it was too easy you can see how this type of puzzle can be extended by looking at the Starter for September 18^{th}.

That’s all for now. Have a worthwhile, satisfying and productive September,

John

Ps The combination locks on safes should really be called permutation locks because it does matter what order the digits are entered.