I was standing with a dozen or so other people waiting for my coffee this morning as the woman behind the counter called out “regular latte”, “long black” and so forth. As I stood in my pre-caffeinated blur I hoped that no one else wanted a large capuccino because I couldn’t cope with fighting over whose it was. No one did. In fact, it hardly ever happens so I started thinking about the numbers.

There are about 15 different types of coffee/tea/hot chocolate on offer in various combinations. Some are only available in small size or only without milk and so forth so I am going to assume that for any different combination, two thirds of the previous set will apply. An arbitrary amount but probably not too far out. So I work it out like this:

Basic combinations 15
times 1.6 for large/small 24
times 1.6 for white/black 38
times 1.6 for skim milk 61
times 1.6 for soy milk 98
times 1.6 for sugar 157

This ignores people who ask for two or more sugars, or extra milk or some other combination I haven’t thought of. Then there are people who buy two or more coffees at the same time for which there is also no confusion.

I know the figures are a serious fudge. For instance, I think there might be a problem with the way I work out white/black/skim/soy but, even so, it is far more amazing that I have encountered a case of the same order than the reverse.

Just goes to show – we have a poor intuitive understanding of probability. Add to that in my case poor mathematical skills (see the above calculation) and no caffeine it is hardly surprising I got it wrong.

I need more coffee.

This entry was posted on Thursday, April 10th, 2008 at 1:38 pm and is filed under Science. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

Comments are closed.

April 2008
« Mar   May »