This coffee-themed puzzle is baffling the entire internet - can you solve it?

If you’ve not had enough coffee yet this morning, hold tight: this puzzle is probably going to BLOW YOUR MIND by which I mean MILDLY IRRITATE YOU FOR SEVERAL MINUTES BEFORE YOU FORGET YOU EVER SAW IT TO BEGIN WITH.

The image, posted by Twitter user @_herbeautyxo, shows a Chemex flask pouring into the top of a series of intricate pipes, all leading into four cups: 4, 9, 5 and 7.

The tweet poses one simple question: which cup will get the coffee first? 

And people were… confused. And… annoyed. 

(Wrong.)

(Also wrong.)

Once you’ve heard the answer, though: it’s really bloody obvious. 

At first glance it may look like cup number 9 will be first - it’s closest to the top, after all, but on closer inspection, that’s impossible: the pipe is closed off. Pipes are also closed off for cups 4 and 7… meaning the only cup that’s going to be filled at all is number 5. 

Bet you feel like an idiot now, don’t you.