316.Spotted at the Gym
★★★conditional probabilityCitadel Securities
James always goes to the gym on Mondays and Tuesdays. On each of the other five days he goes independently with probability 0.3. On a uniformly random day of the week he is spotted at the gym. What is the probability that the day is Monday?
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Weight each day by how likely it was to produce a sighting, then normalise across the week.
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