sample mean

Assume that the weights of 3,000 students at a university are normally distributed with mean 150 pounds and a standard deviation of 2.72 pounds. How many samples would you expect to find the mean between 147 and 155 pounds? => 83 or 82 or 84 or 81..

Which of the following statement(s) is/are true? I. The population mean is represented by the Roman letter X ‾ . The sample mean is represented by the Greek letter μ . II. The measures that determine the spread of the data values are called measures of dispe..

A soft drink company claims that the mean quantity of soft drink in a tin is 300 ml with a standard deviation of 5 ml. A random sample of 65 bottles from a shipment had a mean of 296.5 ml. Is the shipment is significantly different from the standard at the 0.05 level o..

In a statistical hypothesis testing, the standard deviation of the population is 8, H 0 : μ ≤ 100 and H 1 : μ > 100. Which of the following is true for the sample mean ( X ‾ ) to reject the null hypothesis(H 0 ) at α = 0.01 for a sample size o..

The average annual salary in a district is $30,000. Assuming that the salaries were normally distributed for a certain group of wage earners with a standard deviation of $5,000, what is the probability that for a randomly selected sample of 70 earners the mean salary falls below..

A survey report states that the average coffee consumption of the American adult is 400 cups per annum. The annual coffee consumption of 25 American adults was subjected to a study and it was found that the sample has a mean of 418 cups with a standard deviation of 12 cups. At &..

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 26 persons...

A retail garment shop receives a shipment of trousers, with a standard length of 49.0 in. and a standard deviation of 1.0 inch. A random sample of 32 trousers had a mean length of 48.8 in. Which of the following statements is true? => The sample mean does not..

A retail garment shop receives a shipment of trousers, with a standard length of 49.0 in. and a standard deviation of 1.0 inch. A random sample of 32 trousers had a mean length of 48.8 in. Find the 95% confidence interval. => The interval between 48.65 and 49.35 or The interval ..

A magazine report stated that the average business traveler will spend $180 per week on calls. A sample of 20 business travelers are selected at random and their mean expenses was found as $185 with a standard deviation $15. Is there enough evidence to reject the report at &alph..