A paint company claims their paint will be completely dry within 45 minutes after application. Recently,...
8. A paint line can completely paint a produce with a mean time of 40 minutes with a standard deviation of 12 minutes. Nine items are selected at random to be painted. (a) What is the probability that the mean time to paint them is (b) What is the probability that the mean time to paint the items is (c) How large a sample of items must be taken so that the sample between 35 and 45 minutes? greater than...
An intelligence test that has a maximum time for completion of 45 minutes was recently administered to a group of 21 people. Their respective times for completion (in minutes) were as follows. 24, 26, 31, 32, 33, 34, 36, 36, 37, 38, 38, 39, 39, 41, 42, 42, 42, 42, 43, 44, 44 Frequency 1 1 OLA 20 25 30 35 40 Time for completion in minutes) (a) Which measures of central tendency do not exist for this data set?...
question 5 Question 5 An urban planner is researching commute times in the San Francisco Bay Area Select all that apply. to find out if commute times have increased. In which of the following 10 points situations could the urban planner use a hypothesis test for a population mean? Check all that apply. A. The urban planner asks a simple random sample of 110 commuters in the San Francisco Bay Area if they believe their commute time has increased in...
Question 5 An urban planner is researching commute times in the San Francisco Bay Area Select all that apply. to find out if commute times have increased. In which of the following 10 points situations could the urban planner use a hypothesis test for a population mean? Check all that apply. A. The urban planner asks a simple random sample of 110 commuters in the San Francisco Bay Area if they believe their commute time has increased in the past...
The drying time of a certain type of paint under specified test conditions is known to be normally distributed with mean value 75 min and standard deviation 9 min. Chemists have proposed a new additive designed to decrease average drying time. It is believed that drying times with this additive will remain normally distributed with σ = 9. Because of the expense associated with the additive, evidence should strongly suggest an improvement in average drying time before such a conclusion...
A company that produces cell phones claims its standard phone battery lasts longer on average than other batteries in the market. To support this claim, the company publishes an ad reporting the results of a recent experiment showing that under normal usage, their batteries last at least 35 hours. To investigate this claim, a consumer advocacy group asked the company for the raw data, which are shown to the right. Find a 95% confidence interval and state your conclusion. Explain...
Antipsychotic drugs are widely prescribed for conditions such as schizophrenia and bipolar disease. An article reported on body composition and metabolic changes for individuals who had taken various antipsychotic drugs for short periods of time. (a) The sample of 41 individuals who had taken aripiprazole had a mean change in total cholesterol (mg/dL) of 3.45, and the estimated standard error – - was 3.278. Calculate a confidence interval with confidence level approximately 95% for the true average increase in total...
Page 1 Question 1 Suppose we take repeated random samples of size 20 from a population with a Select all that apply. mean of 60 and a standard deviation of 8. Which of the following statements is 10 points true about the sampling distribution of the sample mean (x)? Check all that apply. A. The distribution is normal regardless of the shape of the population distribution, because the sample size is large enough. B. The distribution will be normal as...
3. Waiting times (in minutes) of customers in a bank where all customers enter a single waiting line and a bank where customers wait in individual lines at three different teller windows are listed below. Find the mean and median for each of the two samples, then compare the two sets of results. Single Line 6.36.3 6.66.6 6.76.7 6.86.8 6.96.9 7.17.1 7.67.6 7.87.8 7.87.8 7.87.8 Individual Lines 4.14.1 5.55.5 6.06.0 6.16.1 6.26.2 7.87.8 7.87.8 8.78.7 9.29.2 10.010.0 The mean waiting...
Winter 2018 AT 103 Test II Chapters 6-11 a( \ 1. The average number of miles that 90 truckers drove in a day was 540 with a standard what is the 99% confidence interval of the true mean number of deviation of 40 miles, miles driven by all truckers? Dr. Christina Cuttleman, a nutritionist, claims that the average number ofcalories in a serving of popcorn is 75 with a standard deviation of 7. A sample of 50 servings of popcorn...