9) Suppose the average price of gasoline for a city in the United States follows a continuous uniform distribution with a lower bound of $3.50 per gallon and an upper bound of $3.80 per gallon. What is the probability a randomly chosen gas station charges more than $3.70 per gallon?

In 1995, the median price of a PC was $1200. Suppose that a random sample of100 persons who bought their PCs during that year recorded the amount spent (byeach of them) on his/her PC. State the approximate sampling distribution of ˆp, theproportion of persons who spent more than $1200 on a PC. Find the probabilitythat more than 60% of this group spent more than $1200.   NOTE: Please explain each part, so the problem can be used as a Study Guide

in "a" the blank is "z" and "t" distribution

Which of the following distributions would be most likely to have a tail, and why?   A. The GPAs of NMSU students, because some students have a 4.0.   B. Class scores on a quiz, with 10 points possible, because the most common scores are 7, 8, and 9.   C. The time it takes to install a new piece of computer software, because usually it’s quick, but occasionally it takes hours or even days.   D. The amount of money you spend each month on food, because food prices change a little from day to day, and sometimes things are on sale.

e) Suppose that weekly household expenditures on petrol are normally distributed, with a mean of $120 and a standard deviation of $50. i. A family is randomly selected. Find the probability that this family spends more than $245 per week on petrol? A 2.5 B 0.0062 C 0.9938 D 0.0202 ii. The government wants to promote public transport and will award a prize to the families who spend the lowest amount on petrol. If the government only wants to give a prize to 10% of households, what is the most that a family is allowed to spend on petrol each week to obtain the prize? A $56 B $184 C $3.50 D $217.60 In a sample of 25 families, what is the probability that the average weekly expenditure on petrol will be less than $105? ii. A 0.0668 B 0.9332 C 0.3821 D 0.6179

The state of California has a mean annual rainfall of 22 inches, whereas the state of New York has a mean annual rainfall of 42 inches. Assume that the standard deviation for both states is 4 inches. A sample of 30 years of rainfall for California and a sample of 49 years of rainfall for New York has been taken. (a) Show the probability distribution of the sample mean annual rainfall for California. 39.9 40.6 41.3 42 42.7 43.4 44.1 inches O -2.1-1.4 -0.7 0 0.7 1.4 2.1 inches O 10 14 18 22 26 30 34 (b) What is the probability that the sample mean is within 1 inch of the population mean for California? (Round your answer to four decimal places.) 0.8490 X inches 19.9 20.6 21.3 22 22.7 23.4 24.1 inches

4. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24 pounds, and the highest is 26 pounds. Each weight is equally likely so the distribution of weights is uniform. A sample of 100 weights is taken. a. What is the distribution for the weights of one 25-pound lifting weight? What is the mean and standard deviation? b. What is the distribution for the mean weight of 100 25-pound lifting weights? c. Find the probability that the mean actual weight for the 100 weights is less than 24.9. 1 I

Historically it has been observed that patients admitted to a certain hospital for treatment of influenza spend a MEAN length of 4.4 days in the hospital. Every flu season, different strains of the flu circulate: Some years the primary strain causes more severe illness (and presumably longer than average hospital stays) and other years less so (meaning presumably shorter than average stays). We assume the hospital stays are NORMALLY distributed. a. A hospital wants to see how this year's flu season compares to previous years. Therefore, state the null and alternate hypotheses that would be used to test whether the hospital is seeing a mean hospital stay that is significantly DIFFERENT than the historical mean of 4.4 days. b. FIFTEEN patients admitted for influenza treatment are then randomly sampled and the length of their hospital stay in days is given below. 4641056443743774 SAMPLE MEAN =? SAMPLE STANDARD DEVIATION =? c. Using the results of part (b), determine what type of test is…

The following table shows the distribution of murders by type of weapon for murder cases in a particular country over the past 12 years. Complete parts (a) Handgun through (e). Weapon Probability 0.478 Rifle 0.023 Shotgun Unknown firearm Knives Hands, fists, etc. Other 0.034 0.145 0.135 0.056 0.129