This is especially true when they use the percentage and the word chance in the same sentence.
We all know that 100% of something is one of whatever that is.
100% of a car is one car, or a car. Notice that I can substiture the word a (or an) for one. These words are actually related, which is the reason why.
So let's turn that around.
I have a possibility of becoming a singer.
I have one possibility of becoming a singer.
I have 100% possibility of becoming a singer.
This doesn't mean I am going to become a singer, it simply means that there's a glimmer of hope is some poor bastard's eye that I have anywhere near the ability to sing and put it to use and record my voice for millions of people to hear.
I have a chance. That's ONE chance... which is to say, a 100% chance, because it's a whole chance.
Okay, so there's a chance that it's going to rain.
This doesn't mean that it will rain for certain, but it's possible. It's a 100% possibility, in fact. This means it's also a 100% chance. One chance is a whole chance, but if it doesn't happen, you can't say you thought it was a certainty.
So why is that weather-people say things like, "There's a 30% chance of rain," or, "There's a 75% chance of snow"?
It's just a partial chance? The fact that one whole chance doesn't mean it's going to happen, only that it could, isn't enough? Do they have to reduce the effectiveness of that chance by cutting it up and saying, "Okay, we have a partial chance of sunshine," or "There's a fraction of a chance to see the moon..."?