Welcome to yet another newsletter from Transum Mathematics. As has become traditional I will start off with the monthly puzzle.

Trains from Punspace station go either north or south. Those going north leave hourly, those going south leave hourly. If I arrive at the station at a random time the probability that the next train to leave will be going north is five times the probability that the next train to leave will be going south. How could that be?

While you are thinking about that here is some news about the latest additions to Transum Mathematics.

Kite Maths is a very visual, practical colourful activity leading to the discovery of important geometrical theorems. A new page of interactive animations created in Geogebra has now been added. These dynamic images are great visual aids for classroom use.

Some excellent interactive activities have been created by an organisation called PhET (Physics Educational Technology) and the mathematical simulations are being added to the Transum website. Founded in 2002 by Nobel Laureate Carl Wieman, the PhET Interactive Simulations project at the University of Colorado Boulder create these appealing Maths and Science simulations. They are based on extensive education research and engage students through an intuitive, game-like environment where students learn through exploration and discovery.

During October the following PhET activities have been added: Area Builder, Grid Arithmetic, Fraction Matcher, and Function Builder. You can find them by searching for activity title using the Transum search box (in the footer of every page) or by looking them up on the relevant topic page.

The activity called Clouds was updated last month. It has now been split into five levels and the higher levels include decimals and fractions. The idea of this activity is that clouds have magically floated across some calculations obscuring one of the numbers. Pupils need to find a strategy for working out what is behind each of the clouds. Teachers will see the link with algebra, rearranging formulae or solving equations.

The Mixed Numbers exercise has also been update. Level 5 now includes a variety of questions with words and diagrams! You as the teacher can decide whether pupils should be using this exercise to practice their pen and paper techniques or use it as a calculator exercise, making sense of the calculator’s strange fraction notation.

Coming very soon (hopefully by the end of this week) are some GCSE(9-1) practice papers for pupils on a Foundation level course. Each Weekly Workout contains 7 exam-style questions. The first six can be answered online but the seventh requires the student to draw something that needs the teacher to check.

The answer to this month’s puzzle is best understood by considering what the timetable for departures might look like. If the northbound trains leave at 10 minutes past the hour and the southbound trains leave at 20 minutes past the hour then there’s only a ten minute window for you to arrive at the station for the next train to be going south. There is however a fifty minute window for arriving to find the next train is northbound. Hence the probability that the next train to leave will be going north is five times the probability that the next train to leave will be going south.

Enjoy November

John

P.S. I don’t understand how to double 2n. It sounds 4n to me.