Juked07
Golden Member
And, I answered that, while also pointing out that percentages are quite often meaningless, as in the case of the OP.
I think it's not obvious that what percentage of a person's math he uses is less interesting than what percentage of some fixed body of mathematical knowledge he use. Knowing someone's use of math on some absolute math scale can be equally meaningless. If someone hardly ever uses math at all, how does it matter how much he learned in the first place? It could matter much more, for someone who only ever learned up to algebra, whether he actually uses concepts like arithmetic on a daily basis.
The former is much more closely related to ideas of whether people spend an appropriate amount of time accumulating knowledge, relative to how much they will use in the future.
The second question might also be very interesting in other contexts, but it doesn't seem clear at all that the answer to the OP's question cannot be interesting.