What price do farmers get for their watermelon crops? In the third week of July, a random sample of 40 farming regions gave a sample mean of x = $6.88 per 100 pounds of watermelon. Assume that σ is known to be $1.92 per 100 pounds. (a) Find a 90% confidence interval for the population mean price (per 100 pounds) that farmers in this region get for their watermelon crop. What is the margin of error? (Round your answers to two decimal places.) lower limit     $ upper limit     $ margin of error     $ (b) Find the sample size necessary for a 90% confidence level with maximal error of estimate E = 0.39 for the mean price per 100 pounds of watermelon. (Round up to the nearest whole number.)farming regions(c) A farm brings 15 tons of watermelon to market. Find a 90% confidence interval for the population mean cash value of this crop. What is the margin of error? Hint: 1 ton is 2000 pounds. (Round your answers to two decimal places.) lower limit     $ upper limit     $ margin of error     $

The distribution of study times for first-year students follow a Normal distribution with a standard deviation σ = 48 minutes. Suppose a sample of 344 students found that the mean study time for these students was x¯= 170 minutes per week. Use this to find a 94.38% confidence interval to estimate the mean study time for all students. We are 94.38% confident that the mean study time for first-year students is between the following ( answer) minutes and  ( answer) minutes. The answer needs to be the mean study time for first-year students is between what amount of minutes and the following minutes.

The electric cooperative needs to know the mean household usage of electricity by its non-commercial customers in kWh per day.  They would like the estimate to have a maximum error of 0.14 kWh.  A previous study found that for an average family the variance is 4.84 kWh and the mean is 19.1 kWh per day.  If they are using a 80% level of confidence, how large of a sample is required to estimate the mean usage of electricity?   Question 8 options:   45 households   1959 households   949 housholds   405 households

Suppose we wish to calculate a 90% confidence interval for the average amount spent on books by freshmen in their first year at a major university. The interval is to have a margin of error of $2. Assume that the amount spent on books by freshmen has a normal distribution with a standard deviation of $30. How many observations are required to achieve this margin of error?

Suppose that you are designing an instrument panel for a large industrial machine. The machine requires the person using it to reach 2 feet from a particular position. The reach from this position for adult women is known to have a mean of 2.7 feet with a standard deviation of 0.5. The reach for adult men is known to have a mean of 3.1 feet with a standard deviation of 0.7. Both women's and men's reach from this position is normally distributed. If this design is implemented, (a) what percentage of women will not be able to work on this instrument panel? (b) What percentage of men will not be able to work on this instrument panel? (c) Explain your answers to a person who has never had a course in statistics. Click here to view page 1 of the table. Click here to view page 2 of the table. Click here to view page 3 of the table. Click here to view page 4 of the table.

A hiring company claims that the variance of the annual salaries for managers is greater in Florida than Georgia. You select a sample of 28 managers in Florida and find the standard deviation to be $11,000. You select a sample of 24 managers in Georgia and find the standard deviation to be $9,200. At α=0.05, can you support the hiring company's claim?

You want to buy a washing​ machine, and a salesperson tells you that the mean repair costs for Model A and Model B are equal. You research the repair costs. The mean repair cost of 24 Model A washing machines is ​$209. Assume the population standard deviation is ​$20. The mean repair cost of 27 Model B washing machines is ​$215. Assume the population standard deviation is ​$24. At α=0.01, can you reject the​ salesperson's claim? Assume the samples are random and​ independent, and the populations are normally distributed. Complete parts​ (a) through​ (e). ​(a) Identify the claim and state H0 and Ha.   What is the​ claim?     A. The mean repair costs for Model A and Model B are equal.   B. The mean repair cost for Model A is greater than Model B.   C. The mean repair costs for Model A and Model B are different.   D. The mean repair cost for Model A is less than Model B. Let μ1 be the mean repair cost for Model A and let μ2 be the mean repair cost for Model B.…