Think Twice: Simple Puzzles (Almost) Everyone Gets Wrong

Everyone else gets these seemingly simple puzzles wrong. Will you and your friends beat Alex Bellos, creator of the Guardian's Monday Puzzle, at his own game? Alex Bellos knows better than anyone that the puzzles we find irresistible are the ones that deceive us.

Those that seem blindingly, obviously simple – and yet we can’t help but get wrong. These 70 confounding puzzles – which Alex has scoured from across psychology, mathematics, statistics, physics, geography, the science of perception and more – are guaranteed to catch you and your friends off guard. But why are you getting them wrong?

And how can you get them right? Alex delights in tripping us up and then returning us to our feet, explaining how these puzzles work, the biases holding us back – and how to train your brain to avoid being hoodwinked again. A perfect stocking-filler or Secret Santa for adults and kids alike, Think Twice also makes a great family game to play on Christmas Day.

So, pit yourself against Alex's puzzles or play quiz master to friends and family - either way, you’re in for a mind-boggling treat! Think once and you will stumble. Think twice and you are in with a chance.

Now that you’ve been warned, can you prove Alex wrong?