Wednesday, March 26, 2014

Storm in a tea cup

Here's another on my list of "things I wish people wouldn't do".

It starts with exploring something that is largely subjective and then writing a formula to go with it.  The but I don't like is the way it is published, usually featuring the words "mathematicians have created a formula for...", or "scientists have discovered the formula for...".

The worst part of course is that the formulas are often (with a few honourable exceptions) gibberish.

A new low was plumbed with the formula for the "perfect cup of builders' tea".

Have a look at this (taken from the ITV news website):

What could this possibly mean?  Do try and work out what on earth is going on before you read further.

What is the result of this?  What is E ?  How can you multiply that by the sum of q, t and m?

Thankfully the Deccan Herald is on hand to help us out, explaining that:
The final formula for the perfect builders' brew is: 'Perfect cuppa: 2B + 30R + E(m + q + t) + 10W'.
In the formula 2B denotes two minutes of brewing time, 30R is 30 seconds of resting time, E(m + q + t) denotes a big mug, a good quality tea bag and a treat while 10W stands for 10ml milk.
Oh dear.  It sounds as if they played with lots of different variables and tested lots of different ways of making tea, using willing builders as tea-drinking judges.  In the interview I heard with the students on the radio earlier today the journalist expressed surprise that only 10ml of milk was considered optimal, so they have found out something unexpected.

But why-o-why express it as if it were a formula, when it isn't?

I'm off for a cup of coffee to calm down.  Now, where's my calculator and formula booklet?

Monday, March 10, 2014

Shearer vs Savage (3-act-maths)

As part of the Sport Relief charity fundraising, Alan Shearer and Robbie Savage (now football pundits, previously players) are racing each other to sit on half of the seats at Wembley Stadium (the home of football in England).

Seems like a nice 3-act-maths problem to me.

The website for the programme is here.

Act 1
Show video of Robbie Savage sitting on chairs.  What is going on?
What question could we answer?  (how long it will take them to do it seems like an obvious one)
Give an estimate that you know is too high/low.

Act 2
What information do we need?
How long it takes to sit on each seat.  This can be timed from the video clip.
How long it takes to move between rows, blocks, etc.
Whether they will slow down as they get tired, or speed up as they develop a better technique.
How many seat there are in Wembley Stadium.  Wikipedia and the BBC claim 90,000 and appear to be using that as an exact figure.

Act 3
Well, at the moment (10th March 2014) there isn't an Act 3.  I want to use this in class tomorrow so we can then see later in the week how close we were.  Soon there will be an Act 3 video we can use!