solve please minimal explanation required

Question 12

It is claimed that in a bushel of peaches, less than 10% are defective. A sample of 400 peaches is examined and 50 are found to be defective. What is the critical value for = 0.025?

+1.960

1.645

-1.960

-1.645

14.)

A group of statistics students decided to conduct a survey at their university to estimate the average (mean) amount of time students spent studying per week. They sampled 554 students and found a mean of 22.3 hours per week. Assuming a population standard deviation of six hours, what is the 95% level of confidence?

[21.80, 22.80]

[16.3, 28.3]

[21.64, 22.96]

[20.22, 22.0]

15.)

How is thetdistribution similar to the standardzdistribution?

Both are discrete distributions.

Both are skewed distributions.

Both are families of distributions.

Both are continuous distributions.

16.)

A research firm needs to estimate within 3% the proportion of junior executives leaving large manufacturing companies within three years. A 0.95 degree of confidence is to be used. Several years ago, a study revealed that 21% of junior executives left their company within three years. To update this study, how many junior executives should be surveyed?

594

612

709

897

Question 17

The claim that "40% of those persons who retired from an industrial job before the age of 60 would return to work if a suitable job was available" is to be investigated at the 0.02 significance level. If 74 out of the 200 workers sampled said they would return to work, what is our decision?

Do not reject the null hypothesis because -0.879 lies in the region between +2.326 and -2.326.

Do not reject the null hypothesis because -0.879 lies in the region between +2.5760 and -2.576.

Reject the null hypothesis because 37% is less than 40%.

Do not reject the null hypothesis because 37% lies in the area between 0% and 40%.

Question 18

A university surveyed recent graduates of the English Department for their starting salaries. Four hundred graduates returned the survey. The average salary was $25,000. The population standard deviation is $2,500. A 95% confidence interval is constructed. What does the confidence interval mean?

The population mean is in the interval.

The population mean is not in the interval.

The likelihood that any confidence interval based on a sample of 400 graduates will contain the population mean is 0.95.

There is a 5% chance that the computed interval does not contain the population mean

Question 19

Define the level of significance.

It is the probability of a Type II error.

It is the probability of a Type I error.

It is azvalue of 1.96.

It is the beta error.

Question 21

Suppose 1,600 of 2,000 registered voters sampled said they planned to vote for the Republican candidate for president. Using the 0.95 degree of confidence, what is the interval estimate for the population proportion (to the nearest 10^thof a percent)?

78.2% to 81.8%

69.2% to 86.4%

76.5% to 83.5%

77.7% to 82.3%

Question 22

A machine is set to fill the small-size packages of M&M candies with 56 candies per bag. A sample revealed: three bags of 56, two bags of 57, one bag of 55, and two bags of 58. To test the hypothesis that the mean candies per bag is 56, how many degrees of freedom are there?

9

1

8

7

Question 23

Which of the following is NOT necessary to determine how large a sample to select from a population?

The level of confidence in estimating the population parameter

The size of the population

The maximum allowable error in estimating the population parameter

An estimate of the population variation

question 24

For a null hypothesis, H₀: = 4,000, if the 1% level of significance is used and thez-test statistic is +6.00, what is our decision regarding the null hypothesis?

Do not reject H₀.

Reject H₀.

Reject H₁.

None Apply.

Question 25

The average cost of tuition and room and board at small private liberal arts colleges is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let = 0.05. What is thep-value for this test?

0.0000

0.0124

0.0500

0.4938