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# The columns

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### #1 satrapis

satrapis

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Posted 29 June 2014 - 08:00 PM

In a plot there are 2 columns whose distance is 2 units of length. A car is moving in such a way that at any time is 1 unit of length away from at least one column and a second car is moving so that its distances from the columns have a sum of twice the distance between them (columns). We throw 10 pieces of paper, which have a picture of a face on them, in the plot and fall within the range of movement of the second car, but not uniformly. We pick a random piece of paper.

a) What is the probability that the piece of paper has fallen within the range of movement of the second car but outside the movement area of the first car and the face on it is looking left (left and right don't have the same probability)?

b) One of the drivers half-closes one of  his eyes. If we throw a very small piece of paper (in the range of movement of the second), (at random), what is the probability that the piece of paper gets into the half-closed  eye of the driver?

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