Basic probabilities
Words like 'certain', 'likely' and so on, may not mean the same to everyone.
We need to be more precise about how likely something (an outcome) is to happen.
The probability of an outcome can have any value between 0 (impossible) and 1 (certain). It may be a fraction, decimal or percentage.
When different outcomes from an event are possible, you can use a formula to calculate the probability of outcomes.
\(probability\,of\,an\,outcome =\)
\(\frac{{number\,of\,ways\,the\,outcome\,can\,happen}}{{total\,number\,of\,possible\,outcomes}}\)
When you throw a fair die there are six possible outcomes: 1, 2, 3, 4, 5 or 6.
There are three ways of getting an odd number (1, 3 or 5).
So the probability of getting an odd number = the number of ways of getting an odd number \(\div\) total number of possible outcomes.
\(= \frac{3}{6} = \frac{1}{2}\) or \(0.5\), or \(50\%\).