sample confidence intervals

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..

90% confidence interval of a population mean(μ) worked out on a sample size of 50 is, 50 < μ < 56. What is the likely 90% confidence interval of the mean of the same population worked out on a sample size of 100? => 25 < &mu..

The number of ATM transactions of a bank per day were recorded at 12 locations in a city. The mean of the sample was 88.5 transactions, with a sample standard deviation of 42. Find the 98% confidence interval of the true mean. => 19.06 < μ < 157.94 o..

A random sample of 86 days taken at a large hospital shows that an average of 32 patients were treated per day. The 95% confidence interval of the mean number of patients treated each day at the hospital is between 30 and 34. Find the 95% confidence inte..

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 h..

In a random sample of 25 trees, the variance in height was found to be 6.9. Find the 95% confidence interval for the standard deviation. Assume that the variable is normally distributed. => between 4.9 and 13.7 or between 4.2 and 13.4 or between 5.5 and 14.1 or between..

95% confidence interval of a population mean(μ) with a sample size of 60 was found out as 14.5 < μ < 17.6. Another study calculated the 95% confidence interval as 14.3 < μ < 17.8. Which among the following can be the possible ..

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..

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..

Based on a sample of 150 U.S couples, it was found that in 108 couples the children are taller than the couples. Find the 95% confidence interval for the proportion of all U.S couples where children are taller than the parents. => 68.3% < p < 75.7% or 64.8% < ..