Keeping score on a web app

Hi, I'm part of a team trying to make a web app that basically presents the user with a bunch of different medical-based multiple choice questions. Each question is its own html file. We want to have another html page that displays the user's scores for each question depending on whether they got the question right in one try (1 point) or multiple tries (we take off points for incorrect tries).

How do we tally the overall score of the user? We know we're going to have to use variables in javascript but we don't know how to tally the score across all the different html pages.

We understand that it would be easy to just have all the questions in one html file, use one javascript file to keep track of the score and then notify the user at the end. We're wondering if it's possible for each question to be its own separate page and still keep track of the user's performance using one javascript file.