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Confidence Interval

Confidence Interval and Statistical Analysis

Find the confidence interval and conduct statistical analysis for the given problems. 6. A producer of a juice drink advertises that it contains 10% real fruit juices. A sample of 75 bottles of the drink is analyzed and the percent of real fruit juices is found to be 6.5%. If the true proportion is actually .10, what is th

Probability/Confidence Level

1) Megacorp wants to determine whether the mean of all one-day travel expenses in Moscow exceeds $500. A simple random sample of 35 one-day travel expenses is obtained from Megacorp travel expense files. The average one-day Moscow expense was found to be $538 with a standard deviation of $41. a) Calculate the probability of

Statistic problem

2 Questions: 3) Using the CIELO data, calculate 95% and 99% confidence intervals for the percentage intending to purchase the CIELO. (see attachment for full question) -------------------------------------------------- 3) Using the CIELO data, calculate 95% and 99% confidence intervals for the Percentage intending to purcha

Confidence interval, Testing of Hypothesis

1)      Calculate 95% and 99% confidence intervals for the means selling price of Vehicles sold by Winter Pontiac. 2)      Test the hypothesis that the mean selling price of automobiles sold by Winter Pontiac is less than $25,000. Use alpha= .05 To solve the problem 1 and 2 below use the following table

Confidence interval level

I have an opinion poll perfomed on 2 different population sizes, 900 and 10,000 with a 95% confidence level (Confidence Interval details have been computed) for each population. Opinion Poll Surveyed 900 Surveyed 10000 Invalid intelligence 52% 468 Invalid Intelligence 52% Proportion 0.52 Proportion 0.52

Test a Hypothesis and Confidence Interval

Case Analysis: Riverside Chamber of Commerce ABC Corporation of California publishes a variety of statistics, including the number of individuals who got a new job during the past 12 months and the mean length of time the individuals have been on the job. The Statistical Analysis Department of ASBC Corporation reported that th


4.) 20 rivets out 100 in a new box that we tested had break strength below the desired level. Since this is a critical part for assembly, we want to be 99% confident of how many rivets are below the desired level. Calculate the confidence interval of the percentage of rivets that are below the desired level. 5.) We expect a 1

Statistics: Confidence Interval and Decision Making

Tourism is one consideration for CoffeeTime's future. A survey of 1,233 visitors to Mumbai last year revealed that 110 visited a small café. Use a 0.05 significance level to test her claim. Would it be wise for her to use that claim in trying to convince management to increase their advertising spending to travel agents? Ex

Comparisons Involving Proportions and a Test of Independence

Does age make a difference in the amount of savings a worker feels is needed to be secure at retirement? A study by CommSciences for Transamerica Asset Management found that 0.24 of workers in the 25-33 age category feel that $250,000 to $500,000 is enough to be secure at retirement. In the 34-52 age category already 0.35

Confidence intervals for one population mean

For a t-curve with df = 8, find each t-value and illustrate your results graphically. a.The t-value having area 0.05 to its right. b. t 0.10 c.The t-value having area 0.01 to its left (hint: A t-curve is symmetric about 0.) d.The two t-values that divide the area under the curve into a middle 0.95 area and two outsid

Test whether the sample has been drawn from the population.

A Variable has a mean of 100 and a standard deviation of 16. Four observations of this variable have a mean of 108 and a sample standard deviation of 12. Test whether the sample has been drawn from the population. a. Standardized version of x (sample mean). b. Studentized version of x (sample mean).


5. Human body temperatures are normally distributed with a mean of 98.6 degrees F and a standard deviation of 0.72 deg. F. Find the temperature that separates the top 7% from the bottom 93%. 6. In a sample of 49 adolescents who served as the subjects in an immunologic study, one variable of interest was the diameter of skin

Confidence Interval Statistics Claims

1) a statistian claims that the average score on a test of students for students who major in psychology is greater than that of students who major in math results given to 50 students in each group are shown here Is there enough evidence to support the statisticians claim at @=0.01 Show work. Physc Math X1=118

Confidence Interval

Using sample results and level of confidence of 0.01, test to determine whether the figure published by Runzheimer International is too high. Was it a one- or two-tailed test?

Confidence Intervals Probabilities

4) In a survey conducted to determine cost of vacations, 164 individuals were randomly sampled. Each person was asked to assess the total cost of his or her most recent vacation. The average cost was $1,386. Assuming that the standard deviation was $400, find a 94% confidence interval for the average cost of all vacation trips.

Confidence Intervals calculations

I randomly selected 200 likely voters and created a 95 percent confidence interval for the true proportion of voters that will vote for my candidate. My confidence interval has endpoints of 0.39 and 0.45. Given the confidence interval that I created, is my candidate going to win? After constructing the confidence interval I call

Least Square Regression

1.The following data represent the number of calories per serving and the number of grams of sugar per serving for a random sample of high -fiber cerals. Here are the data to test this claim. Calories, x 200 210 170 190 200 180 210 210 210 190 190 200 Sugar, y 18 23 17

hypothesis about the length of words in newspapers

Context: It would normally follow on from work on setting up and testing hypotheses, and statistical analysis. Question: Suresh is comparing magazines and newspapers. He chooses a passage from one newspaper and one magazine. They each contain 100 words and he counts the lengths of all the words. now this is what you have

Finding the best estimate from an average using a confidence limit.

Last year Groton, Georgia had 512 burglaries. The police chief wants to know the average economic loss associated with burglaries in Groton and wants to know it this afternoon. Since there is not time to analyze all 512 burglaries, the department's research analyst selects 10 burglaries at random, which show the following loss