5.24 Grades in a math course. Indiana University posts the grade distributions for its courses online." In one spring semester, students in Math 118 received 16.1% A's, 34.3% B's, 29.2% C's, 9.6% D's, and 9.8% F's. (a) Using the common scale A = 4, B = 3, C = 2, D = 1, F = 0, take X to be the grade of a randomly chosen Math 118 student. Use the definitions of the mean (page 237) and standard deviation (page 245) for discrete random variables to find the mean µ and the standard deviation o of grades in this section. n %3D (b) Math 118 is a large enough course that we can take the grades of an SR.S of 25 students and not worry about the finite populaticn correction factor. If x is the average of these 25 grades, what are the mean and standard deviation of x? ineg 008A (c) What is the probability that a randomly chosen Math 118 student gets a B or better, P(X > 3)?

The football coach randomly selected fifteen players and timed how long each player took to perform a certain drill. The times (in minutes) were: 3.5, 3.3, 3.2, 4.7, 4.4, 3.5, 3.9, 4.5, 4.8, 5.2, 5.4, 4.0, 4.3, 4.1, 5.1 (a) Show that this data approximates a normal distribution.   (b) Determine a 90% confidence interval for the mean time for all players.

The length of fish were measured at 3 different lakes.  Lake 1:  3.5, 4.2, 6.1, 5.2 Lake 2: 5.1, 6.2, 5.3, 2.1 Lake 3: 5.6, 7.1, 2.4, 4.1, 6.2 Enter the test statistic (to 4 decimal places)

Español A r.able indicator of a baby's health is the weight gained in the fir year of the baby's life. Assume that the population of all such weight gains for baby boys is approximately normally distributed. A study claimed that the mean of this population is 3.454 kg. As a practicing pediatrician, you want to test this claim. So, you select a random sample of baby boys, and you record the weight each gained in their first year. Follow the steps below to construct a 95% confidence interval for the population mean of all the weight gains for baby boys in their first year. Then state whether the confidence interval you construct contradicts the study's claim. (If necessary, consult a list of formulas.) (a) Click on "Take Sample" to see the results for your random sample. Take Sample Sample size: 0 Point estimate: 0 Sample standard deviation: 0 Critical value: 0 Enter the values of the sample size, the point estimate of the mean, the sample standard deviation, and the critical value you…

I'm looking for help on the first 3 bullet points please.

What provides a measure of the variance caused by random, unsystematic differences? a. ​the error term ​b. the F ratio ​c. MS ​d. SStotal

During final exam week, Mary had exams in psychology, art history, and biology.  All three distributions had normal distributions.  On which test did Mary do best, relative to her classmates?  On which test did she do worst?    Psychology Art History Biology Mean 84 37 123 SD 14 8 12 Mary’s Score 90 45 145

Use the Normal model N(100,20) for the IQs of sample participants. a) What IQ represents the 15th percentile? b) What IQ represents the 96th percentile? c) What's the IQR of the IQs? a) The IQ representing the 15th percentile is (Round to one decimal place as needed.) ...