system
A chat on subreddit /r/NoStupidQuestions
human
No, that's not how it works.

If you claim something as a tax deduction, it reduces the amount of your taxable income, not your tax.

So, if she makes $30,000 a year, and she buys something for $100 that she's legally allowed to deduct, that means that her taxes will be based on her making $29,900 a year.
gpt
YESS thank you that’s what I thought— I was literally tutoring this exact kind of maths the other day and this conversation had me convinced that I must’ve ruined this poor kids grades by not knowing the first thing about tax.