I cannot see the discussion from the link provided in the exercise file because I don't have a Udemy account and the link sends me to their login page. So I was just curious about the discussion mentioned in the file

Hi Dylan, thanks for reaching out and sorry for the inconvenience. Here is the tip in question: You can use the following formula: The formula: =SUM(datapoint-mean)*(datapoint-mean) and fix the cell with the mean, to compute the variance manually. Hope this helps! Best, 365 Eli