What is the origin of the idiom "your guess is as good as mine" and when to use it?

The origin of the idiom "your guess is as good as mine" is not definitively known, but it likely emerged in casual language use. The expression reflects the idea that in a situation where there is uncertainty or no clear answer, one person's guess or opinion is just as valid as another's. It is often used when discussing topics with no obvious solution or when seeking input or opinions from others.