I need Statistics Help desperately...?

[caffar]

I was using TutorTeddy.. DON'T USE THEM THEY GIVE YOU WRONG ANSWERS. And you pay for the wrong answers! UGH... So I need real help...

1. In 1993, Toyota introduced the Supra sports car which was designed to have 320 horsepower in stock configuration. A computer chip modification for the fuel injection system was later introduced which was claimed to increase horsepower. To check and see if the chip actually does increase horsepower, we sample 6 stock 1993 Supras and record each vehicle's horsepower (the results appear below):
Car # 1 2 3 4 5 6
Stock Hp 315 321 325 318 320 321

Next, technicians install the computer chip in each of the 6 vehicles' electronic injection systems and then record the horsepower of each (the results appear below):
Car # 1 2 3 4 5 6
Mod Hp 320 320 328 325 323 323

Does it appear that there is an average horsepower increase associated with the chip modification? Select the appropriate critical value (CV), test statistic (TS), and decision below. (Use ? = .05).
A. CV = -1.8125, TS = -1.72, Fail to Reject Ho
B. CV = -2.0150, TS = -2.86, Reject Ho
C. CV = 2.0150, TS = -2.86, Fail to Reject Ho
D. CV = -2.1318, TS = 2.29, Reject Ho

2. Many young adults are choosing to live at home with their parents following college in order to start a career and build some savings. Independent random samples of young adults, 25–34 years old, were obtained and the residence of each was recorded. Of the 226 women, 18 were living at home, and of the 254 men, 36 were living at home. Suppose = 0.01.
Is there any evidence to suggest that the proportion of young women living at home is less than the proportion of young men living at home?

3. A psychologist is studying the effect of belly stars on Sneetches. A random sample of 4 Sneetches is drawn and a test of self-image is given to each Sneetch before and after having their belly star status changed. (If the Sneetch initially had a star, it was removed, if they did not have a star, one was created on them using the patented “Star-off/Star-on” procedure.) From the sample data below construct a 98% confidence interval on the population mean change in self-image associated with a star status change.
Sneetch # 1 2 3 4
Image Score Before 120 88 100 25
Image Score After 130 100 110 55

A. (-37.5519, 6.5519)
B. (-30.7625, -0.2375)
C. (-26.7977, -4.20232)
D. (-23.4535, -7.5465)

4. If two samples are combined by matching each individual or object in sample 1 with a similar object/individual in sample 2, the resulting single sample is:
A. a combinatorial data set.
B. an independent sample.
C. a qualitative data set.
D. a paired data set.

5. Subject 1 2 3 4 5
Before Treatment 332.5 289.3 288.2 268 278.0
After Treatment 317.3 302.5 312.9 325.4 267.3

Assume normality and consider the hypotheses: H0: (mewD) = 0; Ha: (mewD) < 0

Is there evidence to suggest than population mean before treatment is less than population mean after treatment?

6. Two hospitals share responsibility for a very poor area of a major city. Both are required to treat patients regardless of their ability to pay. Hospital 1 claims that their ER treats a higher percentage of non-paying patients than hospital 2. From a random sample of 200 ER cases from hospital 1, 122 were unable to pay. An independent sample of 180 ER cases from hospital 2 has 108 that were unable to pay. Construct a 99% confidence interval on the population difference in proportion of non-paying patients.
A. (-.1194, -.1394)
B. (-.0884, .1084)
C. (-.1553, .1753)
D. (-.1068, -.1268)

8. Two hospitals share responsibility for a very poor area of a major city. Both are required to treat patients regardless of their ability to pay. Hospital 1 claims that their ER treats a higher percentage of non-paying patients than hospital 2. From a random sample of 200 ER cases from hospital 1, 122 were unable to pay. An independent sample of 180 ER cases from hospital 2 has 108 that were unable to pay. Does it appear that hospital 1 has a valid complaint? Select the correct p value and decision below. Use ? = .01.
A. p value = .4211, Fail to Reject Ho
B. p value = .0100, Reject Ho
C. p value = .6100, Fail to Reject Ho
D. p value = .5789, Fail to Reject Ho

[bronsin]

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