See if You Can Solve This 'Coin Flip' Problem That Oxford Asks Its Applicants

So heres the puzzle: Start with a coin. Its not a fair coinmeaning that it doesnt land on each side half the time. (Its whats known as an unfair or biased coin.) When you flip the coin and it lands on heads, you get one dollar. And the game continues: You get to toss the coin again. However, when it lands on tails, , and the game is over.

Got it? Okay, so now: Whats the average amount you can expect to win in this game? In other words, whats the value of it?

While you think that over, well give you a little background on the question. YouTuber Presh Talwalker, who, ahem, walks you through the problem in , says its sometimes described as an Oxford admissions question. That may be truethe Oxford Computer Science Department does but its more likely this is just one of those brain teasers we like to imagine billionaires like and are always posing.

Anyway, if youre ready for the solution, Talwalker lays out the process in his video. It takes about five minutes to explain and uses some lengthy formulas, so were not going to reproduce it here. But if you suspected an appearance by , you were on the right track. Check out the answer in the video below.