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A truly impressive trick. You build a path with cards, randomly, and the magician predicts the end of the race.

Let the participants hold onto the cards, flip them as many times as they like, and arrange them in any order. Then, by asking just one question, determine the total of the numbers they’ve chosen.

Ring ring! Call the cards to find the one the spectator picked.

Does this trick work every time? How can you make it happen? Bring in the clock, and the trick is done.

With a few counters, some multiplications, and just one revealed piece of information, the magic happens!

Can you figure out Gabrielle's birthday?

How can you slice a loaf of bread into 8 pieces using only 3 cuts of a knife?

Happy birthday! A riddle where you have to figure out the maximum number of friends present at a party — with a rather strange clue.

Quick! How can you spot the bronze ring in just three weighings on a balance scale? Luckily for him, Mr. Bolzano is a mathematician and knows exactly how to do it! But how does he do it?

Every summer day, the number of water lilies in the pond doubles. When will the pond be full? Think carefully, as this puzzle can be quite challenging.

How can you find the sum of randomly chosen numbers without even looking at them? Is it a trick? Magic? Pay close attention and try to uncover the mystery!

A number of your choice, jumps of your choice, and the magician finds the sum of 10 numbers without looking. What does he know? How does he do it? It's up to you to find out.