While I don’t have any topics overwhelming my search-engine profile, I do see the rise in people looking up what they need to pass their class, or to get a desired minimum grade. The sorry answer is, they needed to start work sooner. But here’s the formula for working it out, for whatever your course average to date is, whatever score you want, whatever extra credit is available, all that. And here’s tables for some of the common cases, if you’re afraid of the formulas.
And for pleasantly recreational mathematics … I forget which mathematics twitter account that I follow posted the above. But it links to “Ramsey Theory in the Dining Room”. I’d mentioned the field last month because its question about organizing dinner-party guests somehow got a Dear Abby correspondent all angry in the late 70s.
Brian Hayes there ran across an application of the theory that gets away from dinner-party invites and into table place settings. It’s worth a read, particularly for the challenge posed. Hayes thought, briefly, he had solved a question in Ramsey Theory, one that’s easy to understand — you’ll understand the question — but that everyone else in the field has found too hard to answer. He doubted his result, but didn’t think until the next day of why he was wrong. Can you spot where he went wrong? (It’s a subtle flaw in the reasoning, but one an eight-year-old would understand, so I recommend trying to think like one.)