I received the following brain teaser by e-mail and posted it to my brain teasers page. I hadn’t yet figured it out and hoped someone else would help me out.
Well, it’s now exactly one month from when I received it, and yesterday I finally got the answer. I wouldn’t dream of ruining the fun of figuring it out for anyone else, so here’s the riddle sans answer.
A princess is as old as the prince will be when the princess is twice the age that the prince was when the princess’s age was half the sum of their present ages.
What are their ages?
In the end, I had to pull out ye ol’ linear algebra from college to figure out the answer. There are others ways, but I didn’t have much success with them.
I may post a few hints in the comments, depending on how difficult it is for others to figure out.
Spoiler Warning: Answers are in the comments, so if you want to figure it out yourself, don’t scroll down.