I have to do this thing called the Simplex algorithm, basically a giant grid of numbers (easily talking a 9*4 grid here) which you have to do 3 or 4 times per question, changing the numbers completely (but while following the algorithm) with each iteration, often going into decimals or fractions.
Takes about an hour per question.
And THEN you realize you made a mistake somewhere, in the 4 blocks of numbers.
You know how I said an hour per question? well now do it again and get it right this time!
One person took 5 hours on one question and STILL got the wrong answer because they kept making mistakes.
Worst bit of maths I have ever done.
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As for Algebra, I use it all the time, its second nature for me now so I barely notice it.