A study of peach trees found that the average number of peaches per tree was 525. The standard deviation of the population is 105 peaches per tree. A scientist wishes to find the 95% confidence interval for the mean number of peaches per tree. How many trees does she need to sample to obtain an average accurate to within 10 peaches per tree? Hint: Round n up the nearest whole number.
A study of peach trees found that the average number of peaches per tree was 525....
A study of peach trees found that the average number of peaches per tree was 625. The standard deviation of the population is 35 peaches per tree. A scientist wishes to find the 99% confidence interval for the mean number of peaches per tree. How many trees does she need to sample to obtain an average accurate to within 18 peaches per tree? 4 21 23 26
Recent study stated that if a person chewed gum, the average number of sticks of gum he or she chewed daily was 8. To test the claim, a researcher selected a random sample of 36 gum chewers and found the mean number of sticks of gum chewed per day was 9. The standard deviation of the population is 1. a) Find a 95% confidence interval for the average number of sticks of gum he or she chewed daily b) Explain...
You are reading an old report about tree heights in a certain area. The report states (without stating the confidence level) that the true population mean tree height lies between 25.5 m and 29.1 m. The sample size is given as 38 trees, and the document states that the population standard deviation is assumed to be 5.1 m. You wish to determine what confidence level was used to find this confidence interval. What was the sample mean found in the study? What...
Reming The You are reading an old report about tree heights in a certain area. The report states (without stating the confidence level) that the true population mean tree height lies between 25.8 m and 28.0 m. The sample size is given as 37 trees, and the document states that the population standard deviation is assumed to be 5.5 m. You wish to determine what confidence level was used to find this confidence interval. 1. What was the sample mean...
You are reading an old report about tree heights in a certain area. The report states (without stating the confidence level) that the true population mean tree height lies between 24.4 m and 26.8 m. The sample size is given as 31 trees, and the document states that the population standard deviation is assumed to be 6.3 m. You wish to determine what confidence level was used to find this confidence interval. 1. What was the sample mean found in...
You are reading an old report about tree heights in a certain area. The report states (without stating the confidence level) that the true population mean tree height lies between 19.2 m and 23.4 m. The sample size is given as 38 trees, and the document states that the population standard deviation is assumed to be 6.2 m. You wish to determine what confidence level was used to find this confidence interval. 1. What was the sample mean found in...
2. In estimating the mean number of television viewing hours per family per week, a random sample of 400 families yields a mean of 32.6 hours and a standard deviation of 9.9 hours (a) Find a 95% confidence interval for the average number of viewing hours per family per week in the population. Interpret. (b) Find a 99% confidence interval for the average number of viewing hours per family per week in the population. Interpret. (c) Suppose instead only 25...
A market surveyor wishes to know how many energy drinks teenagers drink each week. They want to construct a 95%95% confidence interval for the mean and are assuming that the population standard deviation for the number of energy drinks consumed each week is 0.60.6. The study found that for a sample of 233233 teenagers the mean number of energy drinks consumed per week is 4.14.1. Construct the desired confidence interval. Round your answers to one decimal place.
In a study done by the Scottish government, the average weekly earnings for men were found to be substantially higher than for women. Specifically, the average gross individual weekly income for a random sample of men was £317; for a random sample of women, it was £172 (source: Social Focus on Men and Women, scotland.gov.uk). If the samples included 1500 men and 1200 women, and the sam- ple standard deviations were £89 for the men and £67 for the women,...
A sociologist wants to know the average number of times US families eat their evening meal at home together each week. Data was collected from 50 random families. The sample mean is 3.8 meals per week with a sample standard deviation of 2.5. Construct a 95% confidence interval to estimate the population mean. Then, state this interval below within an interpretive sentence tied to the given context. Redo #19, only this time assume the value $2.5 is the population standard deviation. Then, state this interval...