hw3sols09

# Then the probability that exactly 4 radar sets detect

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Unformatted text preview: is the probability that exactly 4 sets detect the missile? At least one set? we can think of this set-up as a Bernoulli sequence with 5 repetitions. Then, the probability that exactly 4 radar sets detect the missile is: 5 1 0.94 · 0.1 · = 0.32805. At least one set - we computed that probability before: 0.99999. Let X be the number of times a keyword is found. Then P (X ≥ 2) = P (X = 2) + P (X = 3) + P (X = 4) and the probability to ﬁnd a keyword in exactly 2 databases out of a random four databases is P (X = 2) = 5 2 4 2 · = 9 4 10 · 6 = 0.4762. 126 Similarly, P (X = 3) = P (X = 4) = and P (X ≥ 2) = 105 126 5 3 · 4 1 9 4 5 4 · 4 0 9 4 = 10 · 4 = 0.3175 126 = 5 = 0.0397 126 = 0.8333. 4...
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## This homework help was uploaded on 03/11/2014 for the course STAT 330 taught by Professor Staff during the Spring '08 term at Iowa State.

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