20. The lifetimes of refrigerators are normally distributed, and it turns out that a refrigerator that lasts 17years corresponds to z = 1.20. Note that you're not being told the mean and standard deviation becausethe z-score is given to you right there, so you can skip that step. Use the standard normal distribution chartto answer these questions.a) If you buy a refrigerator randomly, what is the probability that it will last 17 years or fewer?b) What is the probability that a random refrigerator will last 17 years or more?c) There are 150 million refrigerators in the U.S. How many are expected to last 17 years or more?

Given Z=1.20 Note: This probability value calculated from standard normal distribution table

Answered: 20. The lifetimes of refrigerators are…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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The amount of time that people spend at Grover Hot Springs is normally distributed with a mean of 64 minutes and a standard deviation of 16 minutes. Suppose one person at the hot springs is randomly chosen. Let X = the amount of time that person spent at Grover Hot Springs . Round all answers to 4 decimal places where possible. a. What is the distribution of X? X - N( b. Find the probability that a randomly selected person at the hot springs stays longer then 79 minutes. c. The park service is considering offering a discount for the 8% of their patrons who spend the least time at the hot springs. What is the longest amount of time a patron can spend at the hot springs and still receive the discount? minutes. d. Find the Inter Quartile Range (IQR) for time spent at the hot springs. Q1: minutes Q3: minutes IQR: minutes
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