Showing all 5 results

Sale!
A study of the ability of individuals to walk in a straight line (” Can we Really walk straight?” Amer. J. of Physical Anthro., 1992: 1927)
$3.00$2.00 
Sale!
You generate a 95% confidence interval for the mean carapace width of dungeness crabs, which is
$3.00$2.00Question:
You generate a 95% confidence interval for the mean carapace width of dungeness crabs, which is 141 +/18 millimeters. Which answer below could you use to improve your estimate (i.e. make your margin of error smaller)?
 Increase the confidence level to 99%.
 Invoke the Central Limit Theorem.
 Increase the number of crabs in your sample
 Eat one out of every 10 crabs in your sample so that you don’t get hungry while you’re making measurements..

Sale!
Suppose a baker claims that the average bread height is more than 15cm. Several of this customers do not believe
$3.00$2.00Question: Suppose a baker claims that the average bread height is more than 15cm. Several of this customers do not believe him. To persuade his customers that he is right, the baker decides to do a hypothesis test. He bakes 10 loaves of bread. The mean height of the sample loaves is 17 cm with a sample standard deviation of 1.9 cm. The heights of all bread loaves are assumed to be normally distributed. The baker is now interested in obtaining a 95% confidence interval for the true mean height of his loaves. What is the lower bound to this confidence interval? cm (round to 2 decimal places) What is the upper bound to this confidence interval? decimal places) cm (round to 2 decimal places)

Sale!
A manufacturer of pharmaceutical products analyses each batch of a product to verify the concentration of the active ingredient. The chemical
$2.00$1.00Question: confidence interval for mean
A manufacturer of pharmaceutical products analyses each batch of a product to verify the concentration of the active ingredient. The chemical analysis is not perfectly precise. In fact, repeated measurements follow a Normal distribution with mean μ equal to the true concentration and standard deviation σ = 0.0076 grams per litter. Three analyses of one batch give concentrations 0.8412, 0.8307, and 0.8321 g/l. To estimate the true concentration, give a 95% confidence interval for μ. (Round your answers to four decimal places.)

Sale!
Based on a random sample of 1040 adults, the mean amount of sleep per night is 7.73 hours
$2.00$1.00Question:
Based on a random sample of 1040 adults, the mean amount of sleep per night is 7.73 hours. Assuming the population standard deviation for amount of sleep per night is 3.5 hours. Construct and interpret a 90% confidence interval for the mean amount of sleep per night.
A 90% confidence interval is ( _____ , ______ )