How would you determine if the toughness of an exam from a hundred years ago matched a modern day one? The pedagogy, tools, and knowledge base differed dramatic

How would you determine if the toughness of an exam from a hundred years ago matched a modern day one? The pedagogy, tools, and knowledge base differed dramatically in the past century. A question might look difficult but be intended as a take-home, be graded differently than binary right-wrong, rely on a trick of an outdated tool (ex. slide rule).