# Qnt 275 week 4 practice set latest 2017 version

## Qnt 275 Week 4 Practice Set Laordeal 2017 Version

*University of Phoenix Material*

Practice Set 4

## Practice Set 4

1. Find z for each of the aftercited belief smooths. Round to two decimal places.

- 90%
- 95%
- 96%
- 97%
- 98%
- 99%

2. For a axioms set obtained from a purposeshort illustration, n = 81 and x = 48.25. It is notorious

that σ = 4.8.

- What is the apex think of μ? Round to two decimal places
- Make a 95% belief gap for μ. What is the inferior designation? Round to two decimal places.
- Make a 95% belief gap for μ. What is the remarkable designation? Round to two decimal places.
- What is the edge of hallucination of think for portio b? Round to two decimal places.

3. Determine the illustration magnitude (nfor the think of μ for the aftercited.

- E = 2.3, σ = 15.40, belief smooth = 99%. Round to the just total compute.
- E = 4.1, σ = 23.45, belief smooth = 95%. Round to the just total compute.
- E = 25.9, σ = 122.25, belief smooth = 90%. Round to the just total compute.

4. Penny or False.

a.The ineffectual theory is a demand environing a population parameter that is productive to be spurious until it is visible spurious.

A. True

B. False

b. An opinion theory is a demand environing a population parameter that earn be penny if the ineffectual theory is spurious.

A. True

B. False

c. The censorious apex(s) sunder(s) is some of the area underneathneath a classification flexion into repudiation and nonrepudiation climes.

A. True

B. False

d. The view smooth, denoted by α, is the likelihood of making a Type II hallucination, that is, the likelihood of throw-bying the ineffectual theory when it is actually penny.

A. True

B. False

e. The nonrepudiation clime is the area to the just or left of the censorious apex where the ineffectual theory is not unusual.

A. True

B. False

5. Fill in the utter. Thelevelofsignificanceinatestofhypothesisistheprobabilityofmakinga**________**.Itistheareaundertheprobabilitydistributioncurvewherewereject*H*0.

A. Type I hallucination

B. Type II hallucination

C. Type III hallucination

6. Consider H0: μ = 45 versus H1: μ < 45. A purposeshort illustration of 25 observations performed a illustration balance of 41.8. Using α = .025 and the population is notorious to be normally exclusive delay σ = 6.

- What is the appreciate of z? Round to two decimal places.
- Would you throw-by the ineffectual theory?

- Reject Ho
- Do not throw-by Ho

7. The aftercited advice is obtained from two fractions illustrations separated from two normally exclusive populations.

n1 = 18 x1 = 7.82 σ1 = 2.35

n2 =15 x2 =5.99 σ2 =3.17

A. What is the apex think of μ1 − μ2? Round to two decimal places.

B. Construct a 99% belief gap for μ1 − μ2. Find the edge of hallucination for this think.

Round to two decimal places.

8. The aftercited advice is obtained from two fractions illustrations separated from two

populations.

n1 =650 x1 =1.05 σ1 =5.22

n2 =675 x2 =1.54 σ2 =6.80

Test at a 5% view smooth if μ1 is short than μ2.

a) Identify the embezzle classification to use.

- t classification
- normal classification

b) What is the disposal environing the theory?

A. Reject Ho

B. Do not throw-by Ho

9. Using axioms from the U.S. Census Bureau and other sources, www.nerdwallet.com thinkd that because solely the households delay trust card something-dues, the mediocre trust card something-due for U.S. house- holds was $15,523 in 2014 and $15,242 in 2013. Suppose that these thinks were domiciled on purposeshort illustrations of 600 households delay trust card something-dues in 2014 and 700 households delay trust card something-dues in 2013. Suppose that the illustration flag deviations for these two illustrations were $3870 and $3764, respectively. Assume that the flag deviations for the two populations are unnotorious but correspondent.

a) Let μ1 and μ2 be the mediocre trust card something-dues for all such households for the years 2014 and 2013, respectively. What is the apex think of μ1 − μ2? Round to two decimal places. Do not conceive the dollar premonition.

b) Construct a 98% belief gap for μ1 − μ2. Round to two decimal places. Do not conceive the dollar premonition.

- What is the inferior spring? Round to two decimal places.
- What is the remarkable spring? Round to two decimal places.

c) Using a 1% view smooth, can you close that the mediocre trust card something-due for such households was better in 2014 than in 2013? Use twain the p-appreciate and the censorious-appreciate approaches to establish this ordeal.

A. Reject Ho

B. Do not throw-by Ho

** **

10. Gamma Corporation is because the installation of governors on cars driven by its sales staff. These devices would designation the car speeds to a preset smooth, which is expected to better fuel management. The association is planning to ordeal various cars for fuel decay delayout governors for 1 week. Then governors would be naturalized in the similar cars, and fuel decay earn be monitored for another week. Gamma Corporation wants to think the balance contrariety in fuel decay delay a edge of hallucination of think of 2 mpg delay a 90% belief smooth. Assume that the contrarietys in fuel decay are normally exclusive and that earlier studies insinuate that an think of sd=3sd=3 mpg is reasonable. How abundant cars should be ordealed? (Note that the censorious appreciate of tt earn await on nn, so it earn be compulsory to use tribulation and hallucination.)