A botanist collected on leaf at random from each of 10 randomly selected mature maple trees of the same species. The mean and the standard deviation of the surface areas for the 10 leaves in the sample were computed. Assume the distribution of surface areas of maple leaves is normal. What is the appropriate method for constructing a one-sample confidence interval to estimate the population mean surface area of the species of maple leaves, and why is the method appropriate?
The t-interval is appropriate, because the population
standard deviation is not known (not provided in this
question).
(Also, the t distribution is apt for samples having small sample
size.)
A botanist collected on leaf at random from each of 10 randomly selected mature maple trees...
A consumer affairs investigator records the repair cost for 16 randomly selected VCRs. A sample mean of $77.34 and standard deviation of $24.56 are subsequently computed. Determine the 80% confidence interval for the mean repair cost for the VCRs. Assume the population is approximately normal. Step 1 of 2: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places. Answer(How to Enter) 2 Points T Tables Keypad
A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, x, is found to be 106, and the sample standard deviation, s, is found to be 10. (a) Construct a 90% confidence interval about u if the sample size, n, is 22. (b) Construct a 90% confidence interval about u if the sample size, n, is 27. (c) Construct a 99% confidence interval about u if the sample size, n, is...
A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, x, is found to be 115, and the sample standard deviation, s, is found to be 10 (a) Construct a 98% confidence interval about if the sample size, n, s 14 (b) Construct a 98% confidence interval about μ if the sample size, n, is 19 (c) Construct a 99% confidence interval about if the sample size, n, s 14 (d)...
A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, x, is found to be 109, and the sample standard deviation, s, is found to be 10 (a) Construct a 98% confidence interval about if the sample size, n, is 29. (b) Construct a 98% confidence interval about if the sample size, n, is 13. (c) Construct an 80% confidence interval about if the sample size, n, is 29. (d) Could...
6.5 6. (10 points) The football coach randomly selected ten players and timed how long each player took to perform a certain drill. The times in minutes) were: 12.9 13.3 13.3 7.7 11.7 9.9 125 10.8 12.2 Assume that the population is normally distributed. a) Check assumptions and choose an appropriate interval procedure b) Use 1-var-stats to find the sample mean and the sample standard deviation c) Find a 95% confidence interval for the mean time for all players. Please...
Consider a 90% confidence interval for µ not known. For which sample size, n = 10 or n = 20, is the confidence interval longer? Critical Thinking Lorraine computed a confidence interval for µ based on a sample of size 41. Since she did not know α, she used s in her calculations. Lorraine used the normal distribution for the confidence interval instead of a Student's t distribution. Was her interval longer or shorter than one obtained by using an...
A random sample of 88 women showed that the mean number of children reported was 1.58 with a standard deviation of 1.8. (interestingly, a sample of 88 men showed a mean of 1.3 children.) Complete parts (a) through (c) below EEB Click the lcon to view the ttable. Find a 95% confidence interval for the population mean number of children for women. Because the sample size is so large, you can use 1.96 for the critical value of t (which...
Suppose a random sample of 17 is selected from a normal distribution and the sample mean x-bar = 102.5 and the sample standard deviation Sx = 4.3. Is this a z distribution or a t distribution? A. t distribution with 17 degrees of freedom B. t distribution with 16 degrees of freedom C. z distribution D. Cannot be determined Part b construct a 96% confidence interval for the population mean A. 100.17 to 104.83 B. 100.36 to 104.64 C. 100.00...
A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, X, is found to be 110, and the sample standard deviation, s, is found to be 10 (a) Construct an 80% confidence interval about p if the sample size, n, is 14 (b) Construct an 80% confidence interval about if the sample size, n, is 18. (c) Construct a 98% confidence interval about if the sample size, n, is 14. (d)...
simple random sample of size n is drawn from a population that is normally distributed. The sample mean, X. is found to be 111, and the sample standard deviation is found to be 10. a) Construct a 95% confidence interval about if the sample size, n, is 28. b) Construct a 95% confidence interval about if the sample size, n, is 11 c) Construct a 90% confidence interval about if the sample size, n, is 28 ) Could we have...