Self Check 18

Question # 00020613 Posted By: mabelson Updated on: 07/23/2014 12:51 PM Due on: 07/24/2014
Subject Statistics Topic General Statistics Tutorials:
Question
Dot Image

Which of the following statements are true?

The sampling distribution of the difference between two proportions will always be normal.
When comparing two population proportions, either sample proportion can be used as the unbiased estimate of the true population proportion.
None of the above are true.
If sample sizes are large enough, and if the population is large compared to the sample, we can compare two proportions using a normal approximation to the binomial.
When you're doing inference for two proportions, the number of degrees of freedom is one less than the smaller of the two sample sizes.
2.

A random sample of 384 people in a mid-sized city (city one) revealed 112 individuals who worked at more than one job. A second random sample of 432 workers from another mid-sized city (city two) found 91 people who work at more than one job. Find a 99% confidence interval for the difference between the proportions of workers in the two cities who work at more than one job.

(0.021, 0.141)
(0.003, 0.159)
Sample sizes aren't large enough to justify using z-procedures
(0.031, 0.131)
(-0.159, 0.004)
3.

We guess, based on historical data, that 30% of graduating high-school seniors in a large city will have completed a first-year calculus course. What's the minimum sample size needed to construct a 95% confidence interval for a proportion with a margin of error of 2.5%?

1286
1537
1533
1223
1291
4.

Your mathematics instructor claims that, over the years, 88% of his students have said that math is their favorite subject. In this year's class, however, only 21 out of 32 students named math as their favorite class. The teacher decides to conduct a test of the hypothesis H0 : P = .88. What's the correct value of the standard deviation of ? for this test.

0.073
0.064
0.045
0.057
0.088
5.

Your mathematics instructor claims that, over the years, 88% of his students have said that math is their favorite subject. In this year's class, however, only 21 out of 32 students named math as their favorite class. The instructor decides to construct a confidence interval for the true population proportion based on the sample value. What's the correct value for the standard error of SE in this case?

0.057
0.045
0.084
0.088
0.064

Dot Image
Tutorials for this Question
  1. Tutorial # 00020014 Posted By: sharpbrain Posted on: 07/23/2014 02:42 PM
    Puchased By: 3
    Tutorial Preview
    The solution of SELF CHECK 18 (SCORE 100%) GUARANTEE...
    Attachments
    SELF_CHECK_18.docx (12.59 KB)

Great! We have found the solution of this question!

Whatsapp Lisa