Mistake in terminology on Resume - Need help explaining the mistake

Hi all, I applied to a job about 2 months ago for a CorpFi Internship role. In my resume at the time, I had made a mistake of an incorrect valuation method that is not even applicable to what I had actually been doing. This was because I had completely misunderstood the valuation method at the time and had changed it since then.

However, from the nature of the application I am confident it will be brought up during my interview. What I am asking for is advice on how I can confidently explain the mistake. No, I do not want to figure out a way to "finesse" the question by twisting it further - I know it will make me look worse. I just want to come across as genuine as to why and how I had made the mistake and how it was fixed since then. Unfortunately, this particular firm does not allow me to go back and submit a revised resume.

I would absolutely ding myself in a situation like this. Super frustrated by this mistake, and need help with adequately explaining it when it inevitably comes up in the interview. Please let me know if you need any more explanation or me to elaborate on anything.