I'm trying to analyze two measurements, the number of steps it takes the user to complete a task on a website, and a ranking rubric of 1 - 3 (1 is simple and 3 is considered difficult) for each step of how difficult the task is for them to complete. At the end we are adding up the number of steps and total difficulty, so there will be two totals. What would be the best way to have a final number for each task? I could divide the difficulty ranking by the number of steps but wondered if there's a better way to go about it.
John Brooke's SUS provides a kind of quantitative evaluation and final number/score that could be customized for doing task analysis. Template can be found here: https://www.usability.gov/how-to-and-tools/methods/system-usability-scale.html ...consider leveraging that.
Your metrics probably cannot be easily aggregated into one number. One is subjective (ranking) the other objective (number of steps).
One way to summarize both could be to use a grading system (A+, B, ...) which you devise using a rubric. For instance, you can decide that 3 or less steps and a 1 is considered a A+. Then you could show the distribution for each grade. For instance most people had a B-, whereas the top 15% has A+.