medium Brainteasers
A release-checked medium problem for training Brainteasers.
A linear army of people that is $50$ miles long walks $50$ miles while a horseman gallops from the back of the line to the front and then gallops to the back again. How far (in miles) has the horseman travelled? The answer is in the form $a(b+\sqrt{c})$ for integers $a,b,$ and $c$ with $a$ maximal. Find $abc$.
This Brainteasers problem is tagged Brainteasers. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.
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