問問英文tenses 問題

Your sentence is perfect！

Reasons：
(1) " I am bad at Maths." --- This is a fact which is always true, regardless of time.

(2) " It is difficult for me to work at bank" ---- This is also a fact and is always true, since you are bad at Maths.

這正符合「現在式」的其中一個應用情況 ----事情是 " always true, regardless of time. "

Your sentence is correct in grammar. However, it'd be better if you can say
I'm weak in Maths instead of bad at Maths.

You need not to be good at Maths to work at bank as there are many different posts.

你應該講“It is difficult for me to work at bank because I'm weak at Maths."

Tense 正確.

加油.