I’ve seen this one before in a popular YouTube video that was going round of a builder springing this one on his poor mate who fell for it and after everyone started laughing at him still couldn’t figure it out and still couldn’t after being given a second chance and still.didn’t understand when it was explained to him through steiffked giggling.

I didn’t understand it then until embarrassingly late in to the video and felt bad for the poor guy who obviously cops that shit from his ‘friend’ a lot so the memory and details of it really stuck with me.

I saw this post, saw the title read the first part of the setup, knew something was coming and still fucking guessed 35 and although I knew that that was the trick answer that this is rigged to elicit and knew that I was wrong I still couldn’t figure it out for like several seconds. Something about this pretty simple trick is remarkably effective at short circuiting my brain even when I know the correct answer.