Need Help Statistic/ Math 11 problems
akem_k
11_stat.docx
1.
Round answers to three decimal places.
(i) S.E. =
(ii) 98% error margin is
2.
Round answers to three decimal places.
(i) S.E. =
(ii) 95% error margin is
·
3.
Determine a 98% confidence interval for the population mean number of items returned.
Confidence interval = ( ,
)
4.
An entomologist sprayed 120 adult Melon flies with a specific low concentration of malathion and observed their survival times. The mean and standard deviation were found to be 18.3 and 5.6 days, respectively. Use these data to construct a 99% confidence interval for the true mean survival time. Round endpoints to one decimal place. Confidence interval = ,
days
5.
Please choose A B C D E.
6.
A,B,C
OR D.
7.
The problem gives the population standard deviation σ, the statement of a claim about μ, the sample size n, and the desired level of significance α. Formulate (i) the hypotheses, (ii) the test statistic Z, and (iii) the rejection region.
|
σ = 8.9 |
claim: μ ≠ 78 |
n = 42 |
α = 0.01 |
(i) The hypotheses.
1) H0: μ = 78, H1: μ ≠ 78.
2) H0: μ = 8.9, H1: μ ≠ 8.9.
3) H0: μ = 42, H1: μ ≠ 42.
Answer =
(ii) The test statistic Z.
Answer =
resp_1
(iii) The rejection region.
1) R: |Z| ≥ 1.88
2) R: |Z| ≥ 2.58
3) R: Z ≤ –1.96
Answer =
·
·
8.
Using the table for the t distributions, find the upper 0.00833 point when d.f. = 12. Round your answer to 3 decimal places.
The upper 0.00833 point when d.f. = 12 is
Using the table for the t distributions, find:
The lower 0.25 point when d.f. = 9.
Round your answer to 3 decimal places.
10.
Recorded here are the germination times (number of days) for seven seeds of a new strain of snap bean.
12 16 15 46 17 11 18
Determine a 95% confidence interval for the true mean germination time for this strain. Assume that measurements are normally distributed.
Round to two decimal places.
(,
) days
11.
The monthly rent (dollars) for a two-bedroom apartment on the west side of town was recorded for a sample of ten apartments.
950 745 875 823 1030 920 840 1085 650 895
Obtain a 95% confidence interval for the mean monthly rent for two-bedroom apartments. Assume that measurements are normally distributed.
Round to two decimal places.
(,
)
resp_2
