A random sample of n = 9 scores is selected from a normal distribution with μ = 80 and σ = 12. What is the probability that the sample mean will be between 76 and 84? ​

A waitress keeps track of the tips she earns and knows that her mean tip is 15% with a standard deviation of 4%. Suppose that she uses this information to create a sampling distribution with samples of size 50 What is the probability that a sample of tips will have a mean between 14% and 15.5%?

a random sample of n = 36 students who registered for Introductory Psychology is placed in the online version of the course. At the end of the semester, all students take the same final exam. The average score for the sample is M = 76. For the general population of students taking the traditional lecture class, the final exam scores form a normal distribution with a mean of u = 71. a. If the final exam scores for the population have a standard deviation of o = 12, does the sample provide enough evidence to conclude that the new online course is significantly different from the tra- ditional class? Use a two-tailed test with a = .05. %3D b. If the population standard deviation is o = 18, is the sample sufficient to demonstrate a significant differ- ence? Again, use a two-tailed test with a = ,05. c. Comparing your answers for parts a and b, explain how the magnitude of the standard deviation influ- ences the outcome of a hypothesis test.

The random variable X has a uniform distribution with values between 15 and 25. What is the mean and standard deviation of X?

Suppose a professor uses a normal distribution to assign grades in her math class. • She assigns an A to students scoring more than 1.9 standard deviations above the mean. • She assigns an F to students scoring more than 2.2 standard deviations below the mean. She assigns a B to students who Score between 1 and 1.9 standard deviations above the mean. • She assigns a D to students who Score between 1.2 and 2.2 standard deviations below the mean. • All other students get a C. Use the Cumulative Z-Score Table to answer the following questions. The Z-Score Table can be found below by selecting "Read". Write your answer as a percent using 2 decimal places. What percent of the class receives each grade assuming the scores are normally distributed? Hint % will recieve an A % will recieve a B % will recieve a C % will recieve a D % will recieve an F

A population of values has a normal distribution with μ=89.6 and σ=35.2. You intend to draw a random sample of size n=32.Find P95, which is the mean separating the bottom 95% means from the top 5% means.The mean =

What position in the distribution corresponds to a z-score of z = +2.00?​

About 71% of all female heart transplant patients will survive for at least 3 years. Eighty female heart transplant patients are randomly selected. What is the probability that the sample proportion surviving for at least 3 years will be pq less than 63%? Assume the sampling distribution of sample proportions is a normal distribution. The mean of the sample proportion is equal to the population proportion and the standard deviation is equal to The probability that the sample proportion surviving for at least 3 years will be less than 63% is (Round to four decimal places as needed.) More Clear All Final Check Help Me Solve This View an Example Get More Help - 4:51 PM 73°F Rain coming 4* 10/4/2021 O Type here to search 10/05/17 EGO PrtSc Insert Delete 口回 F10 F11 F12 F7 F8 F9 F6 Esc F2 F4 F5 F1 F3 & Backspace Num Lock 5 6 2 R T. Y U Home G K L Enter F H. J + |I LEGY P * 00 44 %#3 山

If a population forms a normal shaped distribution with µ =40 and σ = 8 and a sample of 16 scores from this population has a mean of 36, would this sample be relatively typical or extreme?

A population forms a normal distribution with a meaning of 85 and a standard deviation of 24 compute the Z score for the sample mean M equals 914N equals 36 what is Z