Glad tidings and welcome to the Transum Subscribers’ Newsletter for December 2018. I am writing it a few days early due to the fact that I’ll be enjoying a weekend break in the sun when I would have normally written this on the first of the month. Lucky me!

Let’s begin with a festive theme. Here is the puzzle of the month:

St Nicolas’ Yuletide Choir is rehearsing daily for the local school’s Christmas assembly. Each member of the choir has blonde hair or blue eyes; One quarter of the members with blonde hair do not have blue eyes and one third of the members with blue eyes have blonde hair.

What percentage of the choir members do not have blue eyes? The answer is at the end of this newsletter.

As soon as November is over it is quite acceptable to have a festive theme to your Maths lessons. To support this you can, starting on the 1^{st} December, open a door of the Maths Advent Calendar and for each of the days leading up to the 25^{th} enjoy a seasonal activity (from the Christmaths collection), laugh at a cracker joke and solve a mathematical word puzzle. Transum subscribers are able to open doors before the corresponding dates by using the unlock button which can be found lower down the Advent Calendar page when you are signed in.

This last month I have been working enthusiastically improving and adding to the resources at Transum.org. I have just finished Parallel Vectors, yet another activity in the Vectors collection. It is a quick, drag and drop, challenge to match vector expressions with others that represent parallel vectors.

I then copied that activity format to produce Parallel Graphs requiring the rearrangement of equations into the y=mx+c format to find their gradients.

A new vector activity that will appeal to a wider range of pupils is called Vector Maze. Already many have earned Transum Trophies for completing it and the optional challenge is to find the shortest route from start to finish. Chick on the instructions tab to see the latest world record.

Convoluted is the name I plucked out of the air for another brand new activity providing practice recognising multiples. There are three levels with the first including multiples of 2 to 5 while the last level includes multiples up to 12. Pupils can time themselves completing a level and work to improve their personal bests.

Don’t forget there’s also an audio version of this newsletter in the form of a podcast. This month the podcast also includes an advert I heard on Heart Radio for Maths teachers which I quite liked.

Thousands of Transum Trophies are earned by pupils each week from locations across the globe. You may be surprised to hear that the top trophy earner (going by the name of Algebromaths) currently has 797 trophies in his or her trophy cabinet. Amazing!

The answer to this month’s puzzle is 10%. Sketch a Venn diagram with two overlapping circles representing blond and blue. Write x in the region representing the fraction of members with blond hair but not blue eyes. Now use the clues in the question to write the fractions of the members in the other two regions in terms of x. Now form an equation showing the three expressions you have written sum to one. Solve the equation to find x, the percentage of the choir members that do not have blue eyes.

Merry Christmas,

John

- Deck the halls with boughs of holly, Fa (La)
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