t test confidence intervals

Select the incorrect statement(s). I. If a confidence interval does not include H 0 , then a hypothesis test will reject H 0 . II. If a confidence interval include H 0 , then a hypothesis test will reject H 0 III.For testing H 0 ..

When should the t distribution be used to find a confidence interval for the mean? => When the sample size of population is greater than 30 and the standard deviation is known. or When the sample size of population is less than 30 and the standard deviation is known. o..

What is meant by 95% confidence interval of the mean? => 95% of the specific sample means will fall within ± 1.96 standard errors of the population mean. or 95% of the specific sample means will fall within ± 2.58 standard errors of the population mean. or There is..

When a 95% confidence interval is calculated instead of a 90% confidence interval with the same sample, the maximum error of estimate will be _____ . => either smaller or larger depending on sample size or the same or smaller or larger..

To calculate the confidence interval for variance or standard deviation, a statistical distribution called ______ is needed. => chi-square distribution or binomial distribution or poisson distribution or multinomial distribution..

Samples of concrete blocks were tested in a lab to determine the crushing strength of the concrete. The crushing strength of block E was missing from the final records. The sample mean of the crushing strength was recorded as 4.45 tonnes/cm 2 . Find the crushing strength of block E and 90..

A sample of the reading scores of 35 sixth graders has a mean of 82. If the 95% confidence interval for the population mean of the reading scores of all fifth graders is between 77 and 87, then which among the following choices represents the 99% confidence interv..

A survey of 120 families showed that at least 78 had a computer at home. Find the 99% confidence interval of the true proportion of families who own a home computer. => 64.5% < p < 65.5% or 5.38% < p < 7.62% or 53.8% < p < 76.2% or 60.6% < p < 69.4%..

The 95% confidence interval for the mean number of tablets in a bottle of calcium tablets is between 149.04 and 150.96. The standard deviation is 3 tablets. Find the size of the random sample that was used to determine this interval. => 40 or 38 or 6 or 150..

The 95% confidence interval for the mean weight of a sack of potatoes is between 4.92 and 5.08. If a random sample of 32 sacks was used to determine this interval, what was the standard deviation? => 0.04 or 0.16 or 3.92 or 0.23..