large confidence intervals

A restaurant owner wishes to find the 99% confidence interval of the mean number of visitors to the restaurant each day. How large the sample must be if he wants to be accurate within 10 persons? A previous study showed that the standard deviation of the visitors was 2..

A researcher wishes to estimate the average daily wage (industrial composite) of industrial workers. A previous study showed that the standard deviation is $23. How large a sample must be selected if he wants to be 99% confident of getting an interval that contains the..

The formula for the confidence interval for a standard deviation is ________ . => III or II or IV or I..

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..

If 95% confidence interval for the average age of the club members is 39 < μ < 41, then which of the following could be 99% confidence interval? => 39.4 < μ < 40.6 or 39.5 < μ < 40.5 or 39 < μ < 41 or 38 < μ < 42 o..

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%..

A university dean wishes to estimate within $200 the true amount of money spent on administration of its colleges by the University each year. If he wants to be 95% confident, how large a sample is necessary? The standard deviation is known to be $1200. => 600 or 1176 or 139 or ..

In a survey it was found that 20 out of 35 small nursing homes and 35 out of 50 large nursing homes had a vaccination rate of less than 90%. At 99% confidence, find the test value and check whether there is no difference in their proportions. => 11.63, the proportions differ or ..

The 95% confidence interval for the mean number of mangoes in a carton is between 48.12 and 51.88. If a random sample of 27 cartons were used to determine this interval, what was the standard deviation? => 2 or 3 or 4 or 5..