Confusion of rotten/healthy in #Notation section. Section should be:
Notation
Suppose that in some forest, 40% of the trees are rotten and 60% of the trees are healthy. There are then 2 rotten trees for every 3 healthy trees, so we say that the relative ratio of rotten trees to healthy trees is 2 : 3 (note that the ":" doesn't signify "division" as it would in French or German). If we selected a tree at random from this forest, the probability of getting a rotten tree would be 2/5, but the odds would be 2 : 3 for rotten vs. healthy trees.
One aspect I find a bit confusing in this explanation: the difference between the notations "3 / 2" and "3 : 2". In my mind, both correspond to "one and a half". But then suddenly I run into 3:2:6 and get pretty confused.
However, after investigating a bit, the usage of the colon ( : ) for division is common in France (I studied most of my Maths in France), but not in English-speaking countries, where / and ÷ are used instead (we would write "3 : 2 = 1,5"). So when you people use ":" you're not talking about division at all, but only ratios, so it makes sense.
I'm not sure this warrants special extra explanations unless other people get confused by the same thing (Apparently Germans use the colon for division too).
The x/y notation is confusing - these ratios aren't probabilities are they?
Confusion of rotten/healthy in #Notation section. Section should be:
Notation
Suppose that in some forest, 40% of the trees are rotten and 60% of the trees are healthy. There are then 2 rotten trees for every 3 healthy trees, so we say that the relative ratio of rotten trees to healthy trees is 2 : 3 (note that the ":" doesn't signify "division" as it would in French or German). If we selected a tree at random from this forest, the probability of getting a rotten tree would be 2/5, but the odds would be 2 : 3 for rotten vs. healthy trees.
One aspect I find a bit confusing in this explanation: the difference between the notations "3 / 2" and "3 : 2". In my mind, both correspond to "one and a half". But then suddenly I run into 3:2:6 and get pretty confused.
However, after investigating a bit, the usage of the colon ( : ) for division is common in France (I studied most of my Maths in France), but not in English-speaking countries, where / and ÷ are used instead (we would write "3 : 2 = 1,5"). So when you people use ":" you're not talking about division at all, but only ratios, so it makes sense.
I'm not sure this warrants special extra explanations unless other people get confused by the same thing (Apparently Germans use the colon for division too).
(I went ahead and added a note on that anyway)