For an aggregate loss distribution: The frequency distribution is negative binomial with r 35 and ß = 2. The severity distribution is uniform on the interval (0, 100]. The frequency and the individual...

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Extracted text: For an aggregate loss distribution: The frequency distribution is negative binomial with r 35 and ß = 2. The severity distribution is uniform on the interval (0, 100]. The frequency and the individual loss sizes are mutually independent. Use the normal approximation to estimate the probability that aggregate losses are between 3000 and 4000.