Problem bank
Problem 183 of 333MediumProbabilityP183
Making change at the box office
Tickets cost $5 and the box office opens with an empty cash drawer.
Ten customers queue in a uniformly random order. Six pay with a $5 bill and four pay with a $10 bill; anyone paying with a ten must get a five back as change. What is the probability that the seller can always give change?
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