Do one of the​ following, as appropriate.​ (a) Find the critical value zα/2​, ​(b) find the critical value tα/2​, ​(c) state that neither the normal nor the t distribution applies. Confidence level 98​%; n=16​; σ is unknown​; population appears to be normally distributed.

A food manufacturer claims that eating its new cereal as part of a daily diet lowers total blood cholesterol levels. The table shows the total blood cholesterol levels​ (in milligrams per deciliter of​ blood) of seven patients before eating the cereal and after one year of eating the cereal as part of their diets. Use technology to test the mean difference. Assume the samples are random and​ dependent, and the population is normally distributed. At α=0.05​, can you conclude that the new cereal lowers total blood cholesterol​ levels? Patient 1 2 3 4 5 6 7   Total Blood Cholesterol (Before) 215 225 235 240 255 260 225   Total Blood Cholesterol​ (After) 214 222 240 237 254 257 222         Let the blood cholesterol level before eating the cereal be population 1. Let the blood cholesterol level after eating the cereal be population 2. Identify the null and alternative​ hypotheses, where μd=μ1−μ2. Choose the correct…

The undergraduate grade point averages​ (UGPA) of students taking an admissions test in a recent year can be approximated by a normal​ distribution, as shown in the figure.   ​(a) What is the minimum UGPA that would still place a student in the top 10​% of​ UGPAs? ​(b) Between what two values does the middle 50​% of the UGPAs​ lie?               3.4042.8Grade point average μ=3.40 σ=0.17 x         A normal curve labeled mu = 3.40 and sigma = 0.17 is over a horizontal x-axis labeled Grade point average from 2.8 to 4 in increments of 0.3 and is centered on 3.40.       ​(a) The minimum UGPA that would still place a student in the top 10​% of UGPAs is nothing. ​(Round to two decimal places as​ needed.) ​(b) The middle 50​% of UGPAs lies between nothing on the low end and nothing on the high end. ​(Round to two decimal places as​ needed.)

A nutritionist claims that the mean tuna consumption by a person is 3.8 pounds per year. A sample of 70 people shows that the mean tuna consumption by a person is 3.5 pounds per year. Assume the population standard deviation is 1.04 pounds. At α=0.09​, can you reject the​ claim?     ​(a) Identify the null hypothesis and alternative hypothesis.     A. H0​: μ=3.8 Ha​: μ≠3.8   B. H0​: μ≠3.5 Ha​: μ=3.5   C. H0​: μ>3.5 Ha​: μ≤3.5   D. H0​: μ>3.8 Ha​: μ≤3.8   E. H0​: μ≤3.5 Ha​: μ>3.5   F. H0​: μ≤3.8 Ha​:μ>3.8   b) Identify the standardized test statistic. z= ​(Round to two decimal places as​ needed.)   (c) Find the​ P-value.   (d) Decide whether to reject or fail to reject the null hypothesis.     A. Reject H0. There is not sufficient evidence to reject the claim that mean tuna consumption is equal to 3.8pounds.   B. Reject H0. There is sufficient evidence to reject the claim that mean tuna consumption is equal to…

​(c) Calcculate d and sd ​(d) Find the standardized test statistic t.

Using the unemployment data provided, investigate the association between the male unemployment rate in 2007 and 2010 for a sample of 52 countries. Complete parts (a) through (4). m Click the icon to view the data table. OC The plot of the residuals against x tends to cluster as x increases, which is a possible violation of the Linearity Conditon. The Normal probability plot indicates that the Normal Population Assumption is satisfied. OD. The plot of the residuals againat x shows no patten, which satisfes the conditions for linear regression. The Normal probability plot indicates that the Nomal Probability Assumption is violated. c) Test an appropriate hypothesis using a- 0,05 to determine it the association is signiftcant. Choose the corect nul and altemative hypotheses. OA Ha: 0 OB. Ho: lo " 0 HA P0 or l 0 O C. Ho Po-0 OD. Ho: la =P HA Po

The undergraduate grade point averages​ (UGPA) of students taking an admissions test in a recent year can be approximated by a normal​ distribution, as shown in the figure.   ​(a) What is the minimum UGPA that would still place a student in the top 15​% of​ UGPAs? ​(b) Between what two values does the middle 50​% of the UGPAs​ lie?               3.3042.6Grade point average μ=3.30 σ=0.16 x         A normal curve labeled mu = 3.30 and sigma = 0.16 is over a horizontal x-axis labeled Grade point average from 2.6 to 4 in increments of 0.35 and is centered on 3.30.       ​(a) The minimum UGPA that would still place a student in the top 15​% of UGPAs is enter your response here. ​(Round to two decimal places as​ needed.)

A population of values has a normal distribution with μ=95.4μ=95.4 and σ=81.4σ=81.4. Find the probability that a single randomly selected value is less than 78.6. Round your answer to four decimal places. P(X<78.6)=P(X<78.6)=  Find the probability that a randomly selected sample of size n=225n=225 has a mean less than 78.6. Round your answer to four decimal places. P(M<78.6)=P(M<78.6)=

A random sample of 130 observations produced a mean of I = 23.5 and a standard deviation s = 2.16. (a) Find a 90% confidence interval for u (b) Find a 95% confidence interval for u (c) Find a 99% confidence interval for u

(b) Let μ1 be the population mean for x1 and let μ2 be the population mean for x2. Find a 95% confidence interval for μ1 − μ2. (Round your answers to two decimal places.) lower limit      % upper limit      %