In testing a certain kind or truck tire over rugged terrain, it is found that 20% of the trucks fail to complete the test run without a blowout. (a) Of the next 14 trucks tested, how many of them would you expect to have blowouts? (b) What is the variance of the number of blowouts experienced by the 14 trucks? What does that mean? (a) trucks are expected to have blowouts. (Type an integer or a decimal. Do not round.) (b) Select the correct choice below and fill in the answer boxes to complete your choice. (Type integers or decimals. Do not round.) O A. The variance is which means that the expected value of the squared deviation from the mean is O B. The variance is which means that the difference between the lowest possible number of blowouts and the highest possible number is

78​% of U.S. adults think that political correctness is a problem in America today. You randomly select six U.S. adults and ask them whether they think that political correctness is a problem in America today. The random variable represents the number of U.S. adults who think that political correctness is a problem in America Find the variance of the binomial distribution.     σ2=nothing   ​(Round to the nearest tenth as​ needed.)

Up-County Associates is hired to estimate the proportion of county households that own three or more automobiles. They conducted their survey using a simple random sample of 250 randomly selected households and found that 23% of those households owned three or more automobiles.    (a)    Is the proportion, 23%, a parameter or a statistic? Explain.       (b)    If Up-County Associates were to continually choose simple random samples of 250 randomly selected households, each time recording the proportion of households in the sample owning three or more automobiles, what would be the “shape” of the resulting distribution of all these sample proportions?  Explain.             (c)    Suppose now that survey company Lower-County Polling also conducted a survey to determine the proportion of county households that own three or more automobiles, but they surveyed only 100 randomly selected households. If Lower-County Polling were also to sample over and over again (using simple random samples…

Question: Recent surveys have shown a decline in the percentage of U.S. households with cable TV. In one city, a simple random sample of 468 households had 117 households reporting they had cable TV, and 351 households reporting they did not. (a) Show the “plug-in” box to represent our best guess for the relative frequency of people with and without cable. (Let 1 correspond to with cable and 0 without). (b) The percentage of households in the city with cable TV is estimated to be ___________%, and this estimate is likely to be off by about ___________% or so.(c) A 90%-confidence interval for the percentage of households in the city with cable TV goes from ___________% to ___________%.

A researcher uses analysis of variance to test for mean differences among three treatments with a sample of n=12 in each statement.The F-ratio for this analysis would have which df values?   df=2,11 df=2,33 df=2,35 df=2,36