P is for probable
17th June 2019
The probability of getting a head when you toss a fair coin is 1/2 – that is, one chance of a head divided by two possible outcomes. This can be written as a fraction, as the number 0.5 (where 1 equals certainty) or as a percentage, 50%. Similarly, most people will understand that, by the same process, if you throw a six-sided die, the probability of a six is 1/6 (around 17%). However, when a colleague says the chance of someone falling from a ladder is “probable” or its casual synonym “likely”, would any two people agree what this means?