# Researchers determined that 60

Researchers determined that 60 tissues is the mean number oftissues(μ) used during a cold. Suppose a random sample of 64Kleenex users (n) yielded the following data on the number oftissues used during a cold: sample Mean (*X bar)* = 57.5,*S* = 4. Suppose the alternative you wanted to test was*H*_{1}: μ ≠ 60. State the correct rejection regionfor α = 0.1.

Select one:

a. Reject *H*_{0} if *t* < -1.6694 or*t* >1.6694.

b. Reject *H*_{0} if *t* > 1.9983 or*t* < -1.9983.

c. Reject *H*_{0} if *t* < -1.6604.

d. Reject *H*_{0} if *t* > 1.6604.

A researcher is attempting to show statistically that the femaleMBA graduates have a significantly lower mean starting salary thanthe male MBA graduates. Which of the following is an appropriate** alternative hypothesis**?

Select one:

a. *H*_{1}: μ_{females} >μ_{males}

b. *H _{0}*: μ

_{females}<μ

_{males}

c. *H _{0}*: μ

_{females}=μ

_{males}

d. *H _{1}*: μ

_{females}<μ

_{males}

The marketing manager for an automobile manufacturer isinterested in determining the proportion of new compact-car ownerswho would have purchased a side curtain air bag if it had beenavailable for an additional cost of $300. The manager believes fromprevious information that the population proportion is 0.30 (π).Suppose that a survey of 100 new compact-car owners is selected (n)and 45 indicate that they would have purchased the side curtain airbags. If you were to conduct a test to determine whether there isevidence that the proportion is different from 0.30, what will beyour test statistic(Zstat) value?

Select one:

a. *3.27*

b. *2.35*

c. *-4.103*

d. *1.091*

If an economist wishes to determine whether there is evidencethat mean family income in a community is more than $50,000

Select one:

a. a two-tail test should be utilized

b. either a one-tail or two-tail test could be used withequivalent results.

c. None of the above.

d. a one-tail test should be utilized.

Researchers determined that 60 tissues is the mean number oftissues used during a cold(μ). Suppose a random sample of 64Kleenex users (n) yielded the following data on the number oftissues used during a cold: Sample Mean ( X bar) = 57.5, *S*= 4. Using the sample information provided, calculate the value ofthe t-test statistic.

Select one:

a. *t* = -4.00

b. *t* = 4.56

c. *t* = -2.5

d. *t* = -5

Answer:

Solution:

Researchers determined that 60 tissues is the mean number oftissues(μ) used during a cold. Suppose a random sample of 64Kleenex users (n) yielded the following data on the number oftissues used during a cold: sample Mean (*X bar)* = 57.5,*S* = 4. Suppose the alternative you wanted to test was*H*_{1}: μ ≠ 60. State the correct rejection regionfor α = 0.1.

**a. Reject H_{0} if t <-1.6694 or t >1.6694.**

**Explanation:**

**Since the alternative hypothesis is two-tailed,therefore, the two critical values at 0.1 significance level fordf=64-1=63 are:**

A researcher is attempting to show statistically that the femaleMBA graduates have a significantly lower mean starting salary thanthe male MBA graduates. Which of the following is an appropriate** alternative hypothesis**?

Answer: **d. H_{1}: μ_{females}< μ_{males}**

**Explanation: Since the claim is that the female MBAgraduates have a significantly lower mean starting salary than themale MBA graduates, therefore, the alternative hypothesis is oftype left-tailed**

The marketing manager for an automobile manufacturer isinterested in determining the proportion of new compact-car ownerswho would have purchased a side curtain air bag if it had beenavailable for an additional cost of $300. The manager believes fromprevious information that the population proportion is 0.30 (π).Suppose that a survey of 100 new compact-car owners is selected (n)and 45 indicate that they would have purchased the side curtain airbags. If you were to conduct a test to determine whether there isevidence that the proportion is different from 0.30, what will beyour test statistic(Zstat) value?

**Answer: a. 3.27**

*Explanation:*

If an economist wishes to determine whether there is evidencethat mean family income in a community is more than $50,000

**Answer: d. a one-tail test should beutilized.**

Researchers determined that 60 tissues is the mean number oftissues used during a cold(μ). Suppose a random sample of 64Kleenex users (n) yielded the following data on the number oftissues used during a cold: Sample Mean ( X bar) = 57.5, *S*= 4. Using the sample information provided, calculate the value ofthe t-test statistic.

**Answer: d. t = -5**

Explanation: