Loading…
Logic, math, everyday and lateral-thinking riddles — each one paired with a step-by-step visual walkthrough of the solution, right in your browser.
Move a stack of disks to another peg, one at a time, never resting a larger disk on a smaller one.
Spot the hidden rule behind 2, 6, 12, 20, 30 and predict the next term.
A bat and ball cost $1.10; the bat costs $1 more. The obvious answer is wrong.
Add 1 to 100 in seconds — the trick a young Gauss reputedly found in class.
One grain on the first square, doubling each square. How much rice by the 64th?
If everyone in a room of six shakes hands once, how many handshakes happen?
1, 1, 2, 3, 5, 8, 13 … the sequence that models breeding rabbits — and appears everywhere.
Why does 1 + 3 + 5 + 7 + … always land on a perfect square? See it, don't prove it.
$27 paid, $2 kept — that's $29. So where is the thirtieth dollar?