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Is A smaller or larger than B?

Two pieces of paper, each have an unknown number written on it. You pick one of them and get see the number. Guess if this number is smaller or larger than the other.

Instinct might say that is fifty-fifty to guess right. But actually there is a strategy to do better than 1/2.

In fact, if the numbers are chosen from Uniform(-1, 1), there is a strategy to guess right with probability 3/4. !!

Hint for general strategy: pick a random number and compare.
Hint for Uniform(-1, 1): Focus on 0 which divides the number line into 2 halves. What can you say about the chance that both numbers fall to the left or right of 0? Anything interesting?

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