Don't get too carried away by the requirement for a strong background in maths. We are not talking about anything beyond GCSE - honestly.
You need to be quick and proficient at elementary mental arithmetic - adding, subtracting, multiplying, dividing - without a calculator - quickly and accurately.
You need to be able to re-arrange elementary algebra - ie, "make 'x' the subject of the following equation" when it is set out as 'y' = something.
And you need to understand sine, cosine, and tangent.
It really doesn't need to be any deeper than that. No calculus. No hyperpolic functions.
I bet you can cope with that. It's being able to calculate quickly rather than the depth of your previous studies that matters. And you can work that up by practice if you want to succeed.
All the best
Paul