Please answer Question 34-37 based upon the following information. Suppose that

Question

Please answer Question 34-37 based upon the following information. Suppose that the amount of time teenagers spend working at part-time job is normally distributed with a population standard deviation of 20 minutes. A random sample of 100 observations is drawn, and the sample mean computed as 125 minutes. The unbiased point estimate of population mean in this case is

20 minutes

100 minutes

125 minutes

unavailable because no confidence level is given

Please answer Question 34-37 based upon the following information. Suppose that the amount of time teenagers spend working at part-time job is normally distributed with a population standard deviation of 20 minutes. A random sample of 100 observations is drawn, and the sample mean computed as 125 minutes. If we want to obtain the interval estimate of population mean at 90% confidence level, which of the following statistic values should be applied?

Z0.1

Z0.05

Z0.025

t0.05, 99

Please answer Question 34-37based upon the following information. Suppose that the amount of time teenagers spend working at part-time job is normally distributed with a population standard deviation of 20 minutes. A random sample of 100 observations is drawn, and the sample mean computed as 125 minutes. The 90% confidence interval estimate of the population mean is

(125 ± 2.56) minutes

(125 ± 3.29) minutes

(125 ± 3.92) minutes

unavailable without statistical software calculation

Please answer Question 34-37 based upon the following information. Suppose that the amount of time teenagers spend working at part-time job is normally distributed with a population standard deviation of 20 minutes. A random sample of 100 observations is drawn, and the sample mean computed as 125 minutes. Given the same 90% confidence, if we want to produce an interval estimate with the desired margin of error, E=2 minutes, the sample size should be at least

271.

484.

852.

1058.

Z0.1

Z0.05

Z0.025

t0.05, 99

Explanation / Answer

1) Since point estimate is unbiassed
Answer: 125 minutes

2) Answer: Z0.05
0.05 to each tail makes up 0.1(significance level)

3) 90% CI = mean +/- Z0.05 * s/sqrt(n) = 125 +/- 1.645*20/sqrt(100) = 125 +/- 3.29

4) E = Z0.05 * s/sqrt(n)
2 = 1.645*20/sqrt(n)
n = 270.6 = 271

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.