MATH302 Week 4 Test questions and answers new 2020-2021 practice docs

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MATH302 Week 4 Test questions and answers new 2020-2021 practice docs Part 1 of 6 - Calculations of Probabilities Questions 2.0/ 3.0 Points Question 1 of 20 0.0/ 1.0 Points The mean yearly ... rainfall in Sydney, Australia, is about 134 mm and the standard deviation is about 66 mm ("Annual maximums of," 2013). Assume rainfall is normally distributed. How many yearly mm of rainfall would there be in the top 15%? Round answer to 2 decimal places. Question 2 of 20 1.0/ 1.0 Points Find P(Z > -.98). Round answer to 4 decimal places. Question 3 of 20 1.0/ 1.0 Points Find P(Z ≥ .42). Round answer to 4 decimal places. Question 4 of 20 1.0/ 1.0 Points Which type of distribution does the graph illustrate? • A. Poisson Distribution • B. Right skewed Distribution • C. Uniform Distribution • D. Normal Distribution 1.0/ 1.0 Points Question 5 of 20 1.0/ 1.0 Points The manufacturer of a new compact car claims the miles per gallon (mpg) for the gasoline consumption is mound-shaped and symmetric with a mean of 27.4 mpg and a standard deviation of 10.2 mpg. If 29 such cars are tested, what is the probability the average mpg achieved by these 29 cars will be greater than 29? Question 6 of 20 1.0/ 1.0 Points The commute time for people in a city has an exponential distribution with an average of 0.66 hours. What is the probability that a randomly selected person in this city will have a commute time between 0.55 and 1.1 hours? Answer: (round to 3 decimal places) . Question 7 of 20 1.0/ 1.0 Points The average lifetime of a set of tires is 3.4 years. The manufacturer will replace any set of tires failing within three years of the date of purchase. The lifetime of these tires is known to follow an exponential distribution. What is the probability that the tires will fail within three years of the date of purchase? • A. 0.5862 • B. 0.4138 • C. 0.4866 • D. 0.7568 Question 8 of 20 1.0/ 1.0 Points The caller times at a customer service center has an exponential distribution with an average of 22 seconds. Find the probability that a randomly selected call time will be less than 30 seconds? (Round to 4 decimal places.) Question 9 of 20 1.0/ 1.0 Points Suppose that the longevity of a light bulb is exponential with a mean lifetime of 7.6 years. 85% of all light bulbs last at least how long? • A. 15.67 • B. 14.42 • C. 9.6318 • D. 10.678 • E. 11.34 Question 10 of 20 1.0/ 1.0 Points The waiting time for a bus has a uniform distribution between 2 and 11 minutes. What is the probability that the waiting time for this bus is less than 5.5 minutes on a given day? Answer: (Round to two decimal places.) . Question 11 of 20 1.0/ 1.0 Points The mail arrival time to a department has a uniform distribution over 5 to 45 minutes. What is the probability that the mail arrival time is more than 25 minutes on a given day? Answer: (Round to 2 decimal places Question 12 of 20 1.0/ 1.0 Points The waiting time in line at an ice cream shop has a uniform distribution between 3 and 14 minutes. What is the 75th percentile of this distribution? (Recall: The 75th percentile divides the distribution into 2 parts so that 75% of area is to the left of 75th percentile) _______ minutes Answer: (Round answer to two decimal places.) Question 13 of 20 1.0/ 1.0 Points A local grocery delivery time has a uniform distribution over 15 to 65 minutes. What is the probability that the grocery delivery time is more than 20 minutes on a given day? Answer: (Round to 2 decimal places.) Question 14 of 20 1.0/ 1.0 Points Miles per gallon of a vehicle is a random variable with a uniform distribution from 22 to 39. The probability that a random vehicle gets between 26 and 31 miles per gallon is: Answer: (Round to four decimal places) . Question 15 of 20 1.0/ 1.0 Points The waiting time for an Uber has a uniform distribution between 5 and 37 minutes. What is the probability that the waiting time for this Uber is less than 13 minutes on a given day? Answer: (Round to two decimal places.) 2.0/ 5.0 Points Question 16 of 20 0.0/ 1.0 Points The average amount of a beverage in randomly selected 16-ounce beverage can is 15.96 ounces with a standard deviation of 0.5 ounces. If a random sample of sixty-five 16-ounce beverage cans are selected, what is the probability that the mean of this sample is less than 16.05 ounces of beverage? Answer: (round to 4 decimal places Question 17 of 20 1.0/ 1.0 Points A certain brand of electric bulbs has an average life of 330 hours with a standard deviation of 35. A random sample of 80 bulbs is tested. What is the probability that the sample mean will be less than 318? • A. 0.0011 • B. 0.9989 • C. 0.0006 • D. 0.0127 Question 18 of 20 0.0/ 1.0 Points The average amount of a beverage in randomly selected 16-ounce beverage can is 16.18 ounces with a standard deviation of 0.38 ounces. If a random sample of eighty 16-ounce beverage cans are selected, what is the probability that mean of this sample is less than 16.1 ounces of beverage? Answer: (round to 4 decimal places) ) Question 19 of 20 0.0/ 1.0 Points The final exam grade of a statistics class has a skewed distribution with mean of 79 and standard deviation of 8.2. If a random sample of 35 students selected from this class, then what is the probability that average final exam grade of this sample is between 76 and 82? Answer: (round to 4 decimal places) Question 20 of 20 1.0/ 1.0 Points The time a student sleeps per night has a distribution with mean 6.15 hours and a standard deviation of 0.5 hours. Find the probability that average sleeping time for a randomly selected sample of 40 students is more than 6.29 hours per night. Answer: (round to 4 decimal places) [Show More]

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