Math Tricks, Brain Twisters And Puzzles -

"Double it," Leo commanded. "Add ten. Divide it by two. Now, subtract the original number you started with." Sam paused, his brow furrowed. "Okay, done." "The answer is five," Leo said instantly.

But Sam wasn’t satisfied. "Fine, try this : A man is looking at a photograph. His friend asks who it is. The man replies, 'Brothers and sisters, I have none. But that man’s father is my father’s son.' Who is in the photo?" Math tricks, Brain twisters and Puzzles

The group gasped. Sam tried it again with three. Then ten. The answer was always five. "How?" "Double it," Leo commanded

The brigade tried for ten minutes, overlapping them, making stars, failing. They were stuck in 2D. Now, subtract the original number you started with

Leo leaned back. "It’s his son. 'My father’s son' is the man himself, so he’s saying 'That man’s father is me .'"

Leo reached out and picked up the picks. Instead of laying them flat, he stood three up to meet at a point, using the other three as a base. He had built a —a 3D pyramid.

"It’s a ," Leo explained. "By adding ten and then dividing everything by two, I’m essentially adding a 'hidden' five that stays behind when you subtract your original number. It’s just logic in disguise."