Records indicate that the mean weight of mature rainbow trout in Eagle Creek is 1.75 kg with a standard deviation of 0.37 kg. After yearsof marked oxygen depletion from pollutants in the creek, you want to perform a hypothesis test to see if the standard deviation, ơ, ofweights has changed. To do so, you measure the weights of 19 randomly chosen mature rainbow trout from the creek and find that thesample standard deviation is 0.49 kg.Under the assumption that current weights of mature rainbow trout in the creek follow a normal distribution, you will perform a chi-squaretest.Find x, the value of the test statistic for your chi-square test. Round your answer to three or more decimal places.2

Given that σ=0.37 , s=0.49 , n=19

Answered: Records indicate that the mean weight…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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Our environment is very sensitive to the amount of ozone in the upper atmosphere. The level of ozone normally found is 6.3 parts/million (ppm). A researcher believes that the current ozone level is at an excess level. The mean of 870 samples is 6.4 ppm. Assume the variance is known to be 1.00. Does the data support the claim at the 0.1 level? Step 2 of 5 : Enter the value of the z test statistic. Round your answer to two decimal places.
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To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a safety engineer conducts braking tests for 35 models of Make A and 35 models of Make B. The mean braking distance for Make A is 41 feet. Assume the population standard deviation is 4.6 feet.The mean braking distance for Make B is 42 feet. Assume the population standard deviation is 4.4 feet. At α=0.10, can the engineer support the claim that the mean braking distances are different for the two makes of automobiles? Assume the samples are random and independent, and the populations are normally distributed. Complete parts (a) through (e). (a) Identify the claim and state Ho and Ha. What is the claim? A.The mean braking distance is different for the two makes of automobiles. This is the correct answer. B.The mean braking distance is the same for the two makes of automobiles. C.The mean braking distance is less for Make A automobiles than Make B automobiles. Your answer is…

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