June 25, 2013

# Maths in the Real World

## I’ll hint at how this works later. Just play for now.

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# How does this work?

Maths goes wrong in the real world when we ASSUME certain parameters are CONSTANTS when they are VARIABLES.

This is how this trick works. We assume the cards above are constant.

Now look at both sets of cards again …………………

## 3. The Trouble with Double

October 12, 2010

Percentages

When the Numbers involved are so SMALL the % Stated is Meaningless.

Newspapers often state that a cancer rate has doubled or increased (See pic) by 28%. Those % changes can be meaningless. For instance, double nothing is still nothing. You need the actual numbers.

Here is a statistic taken from Men’s Health magazine (March 2010). According to the government funded Australian Institute of Health and Welfare the actual number of Australian males who presented with melanoma in 2005 was 6,044

or   0.549  in 1,000

or 1 in 2,000.

If these numbers increase by 28% the number of Australian men presenting with melanoma will be:

0.703 in 1,000

or  ~ 2 in 3,000.

These numbers are not so alarming. Then again would you take any notice of statistics of a magazine that suggests a ‘sonic boom’ from a golf club is causing deafness!!!!!