Definite or indefinite article? [closed]

I really get confused about using 'a' or 'the'.

In this definition taken from Cambridge dictionary

Average: the result you get by adding two or more amounts together and dividing the total by the number of amount.

can I use 'A' before 'result' instead of 'THE' ?

Solution 1:

I've found a good way of making the difference between "a" and "the" is that you use "the thing" when both you and the person you're talking to know or can guess which specific thing you're talking about, and "a" when they can't, either because the specific thing isn't important, or because you're first introducing this thing.

So for example, "a car ran me over" -> we don't care which car it was, just that I was run over. Or, "I met a woman. The woman was blond" -> we do care about this woman, but when I first mention her you don't know about her yet. If I'd said "I met the woman", you'd be thinking "huh they said 'the' so I should know who this woman is. Who is she? I'm confused". In the second sentence however you can guess I'm talking about the woman I met, because "the" means you should be able to tell which woman she is and the woman I've met is the only woman I've mentioned so far. On the other hand if I'd said "A woman was blond" you would assume it's a different woman, or at least that you have no further information beyond the fact that some woman, in the universe of women I might be talking about, was blond.

In this case, how many results can you get by adding two or more amounts together and dividing the total by the number of amounts? There is only one result, and it is this specific result that is called "average", and the writer knows this and wants you to understand it as well. So, "the".

Note that it wouldn't be wrong to use "a" in this case; it would mean that of all the results you can get from the operation described, "average" is one of them. It so happens that there is only one result, but "all" includes "one". So it's literally accurate, but it does suggest that there is more than one result, and it would be more natural to use it if there were many results than if there is just one.

Take the same definition from Wikipedia for example:

In colloquial language, an average is a single number taken as representative of a list of numbers. Different concepts of average are used in different contexts. Often "average" refers to the arithmetic mean, the sum of the numbers divided by how many numbers are being averaged. In statistics, mean, median, and mode are all known as measures of central tendency, and in colloquial usage any of these might be called an average value.

That first sentence uses "a", and indeed it is saying that there are many different ways of making a single number represent a list of numbers, and "average" refers to one of them in a non-specific way. (note also how the first sentence talks about "a single number" and "a list of numbers", while the sentence describing the arithmetic mean talks about "the numbers": it's referring to the numbers in the list mentioned before).