Well, About 3-5 percent of the best students in a cohort can expect to get First Class Honours. It basically means 97th percentile, or 95th percentile, depending on the quality of the students. The 75th to 95th percentile can expect to get Second Class Honours.
Which implies that I can, tentatively, estimate you to be in the top 10% of people who are accepted for a degree. That's really good.
I must admit that this question stunned me. I don't actually know.
...I think we've found the start of the problem. Your foundations have a few holes.
Dividing X by Y, at its core, means that I have X objects, I want to place them in Y exactly equal piles, how many objects do I place per pile? (At least, that's the definition I'd use). In this way, the usefulness of the operation is immediately apparent; if I have six apples, and I want to divide them among three people, I can give each person two apples.
I can use the same definition if I have five apples and three people; then I give each person one and two-thirds apples.
This also works for negative numbers; if I have negative-six apples (i.e. a debt of six apples) I can divide that into three piles by placing negative-two apples in each pile.
Division by zero then becomes a matter of taking (say) six apples, and trying to put them into zero piles. (I hope that makes the problem with division by zero clear).
And yes, there is a fancy algorithm that I can put X and Y in and get the quotient out... but that algorithm is not a particularly good basic definition of division. (Interestingly, I note that your definition jumps straight to setting out separate cases and then trying to apply a different algorithm to each individual case. This would make it very hard to work with in practice; I've worked with division algorithms on computers, and they're far simpler, conceptually, than what you had there. If that's what you've been working with, then I am really not surprised that you've been having trouble with maths).
Now let's see how far this goes...
Define "multiplication", "addition", and "subtraction".
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A list of some posts that are pretty awesome
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