## Thursday 1st October 2020

Another month begins and another newsletter is born. It will start, as always, with the puzzle of the month.

A train leaves Aberdale bound for Bluffington and travels at 90 kilometres per hour. At the same time another train leaves Bluffington bound for Aberdale and travels at 110 kilometres per hour.

How far will the trains be apart half an hour before they meet?

The answer to the puzzle will be at the end of this newsletter but before that here are some of the new arrivals on the Transum website.

Power Shift is a number arranging puzzle involving three powers. Pupils are challenged to make the smallest/largest possible totals in the first couple of levels then specific totals in the other eight levels. At the time of writing 64 trophies have been earned for completing levels.

Doughnut Dissection is an original puzzle dreamed up by a Transum subscriber. It is hoped that pupils will see that finding the prime factors of the given targets is useful in creating the sets of three factors that obey the doughnut directives.

QuotientMaster is the division sequel to the immensely popular Tablesmaster program. Both programs focus on the speed of recall of table facts and encourage pupils to improve on their personal best scores. A detailed breakdown of the time taken to recall particular facts is presented after the twenty questions have been answered so that pupils can focus on their more difficult-to-remember facts.

A new Level 2 has been added to the Angles in a Triangle exercise. It contains some interesting puzzles and some of the questions do require the basics of algebra. A new help video has been created to provide a reminder of some methods used to answer the questions in both levels. The video can be found in the help tab.

New help videos have also been made this month on the topics of Indices and Differentiation. Those videos were made to go in the help pages of the related online exercises.

At the end of this month the Starter of the Day celebrates the dubious festival of Halloween. Five themed problems that show that mathematics doesn’t have to take itself too seriously. Not for pupils who are easily scared!

I remember many years ago some people saying that a ruler was a king or queen and the graduated stick used to measure line segments should be referred to as a rule. I was never very keen on that and now I have discovered that in the dictionary both rule and ruler have one of their many definitions similar to 'a straight usually graduated strip or cylinder of wood, metal etc., used to draw lines or measure distances'. Consequently I will happily continue to use the word ruler despite the fact that elsewhere on the web I find that rule is a ruler with graduations starting at its edge and a ruler's graduations begin a little way in from its edge. Who knew?

There are many other differences of opinion regarding mathematical vocabulary and I am recording my preferences in the Style Guide, a record of standards, preferences and conventions for the content of Transum web pages.

Finding resources on the Transum website has never been easier. The most effective tool is the Topics page. Choose the category you are interested in then get to know the sections of the individual topic page. The Curriculum section allows you to fine tune your searching by age group and learning objective. If all else fails though you could always search by keyword on the main Search page.

Now here’s the answer to the puzzle of the month about the trains travelling between Aberdale bound and Bluffington. Adding the speeds of the trains together gives the relative speed they are approaching each other.

90 + 110 = 200

So with a relative speed of 200 kilometres per hour they will travel 100km in half an hour.

The trains will be 100km apart half an hour before they meet.

If you like challenges involving trains don't miss these Shunting Puzzles.

That's all from me. Enjoy October and stay safe,

John

PS. With Halloween approaching, what happens if you get scared half to death twice?