1. The lengths of pregnancies are normally distributed with a mean of 267 days and a standard deviation of 15 days. If 50 women are randomly selected, find the probability that they have a mean pregnancy between 266 days and 269 days. 2. A car-wash operator counts the number of cars arriving at the premises and finds that, on average, there are 8 per hour. Find the probability that there are at least two cars in the car- wash in any 30-minues period.

1. The lengths of pregnancies are normally distributed with a mean of 267 days and a standard deviation of 15 days. If 50 women are randomly selected, find the probability that they have a mean pregnancy between 266 days and 269 days. 2. A car-wash operator counts the number of cars arriving at the premises and finds that, on average, there are 8 per hour. Find the probability that there are at least two cars in the car- wash in any 30-minues period.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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41 In most of Europe and Asia annual automobile insurance is determined by the bonus malus system. Each policyholder is givena number (state) and the policy premium is determined as a function of this state. A policy holder's state changes from year to year in response to the number of claims made by the policy holder. Suppose the number of dlaims made by a particular policyholder in any given year, is a Poisson random variable with parameter A. Let. sj(k) be the next state of a policyholder who was in state i in the previous year and who made k claims in that year. The following table is a simplified Bonus-Malus system having 4 states Next state if Annual Premium State O claims 1 claim 2 claims 3 or more claims 1 200 1 3 4 250 3 4 4 4. 4. 400 2 600 3 4 4 4. 4 For A=2 A. Find the mean time to retum to state 1 (if you start in state 1): (round to 2 decimals) (round to 2 B. Find the expected annual premium for a random person after it has been with the insurance company for a while:…
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