A researcher wishes to estimate, with 90% confidence, the population proportion of likely U.S. voters who think Congress is doing a good or excellent job. Her estimate must be accurate within 2% of the true proportion(a) No preliminary estimate is available. Find the minimum sample size needed.
(b) Find the minimum sample size needed, using a prior study that found that 28% of the respondents said they think Congress is doing a good or excellent job.
(c) Compare the results from parts (a) and (b).
Answers
The sample size just be 752.
What is confidence interval?
A confidence interval (CI) for an unknown parameter in frequentist statistics is a range of estimations. The most popular confidence level is 95%, but other levels, such 90% or 99%, are occasionally used for computing confidence intervals. The fraction of related CIs over the long run that actually contain the parameter's true value is what is meant by the confidence level. The degree of confidence, sample size, and sample variability are all factors that might affect the width of the CI. A larger sample would result in a narrower confidence interval if all other factors remained constant. A wider confidence interval would also be required by a higher confidence level and would be produced by a sample with (1.645 / 0.03)2 * 0.5 * 0.5
=752
Sample size = 752
= 1 - 0.42 = 0.58
margin of error = E =3 % = 0.03
At 90% confidence level z
Hence, The sample size just be 752.
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a. 51
b. 53
c. 54
d. 55
Answers
Final answer:
The missing number in the sequence is 54.
Explanation:
The missing number in the sequence is 54.
To identify the missing number, we need to observe the pattern in the sequence. The sequence decreases by 12 each time. Starting from 78, we subtract 12 to get 66, then subtract 12 again to get 54, and so on. Therefore, the missing number is 54.
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a. 8 millimeters = ____meters
Answers
Answer:
0.008 meters
Step-by-step explanation:
Answer:
0.008 meters
Step-by-step explanation:
Hope this helps! :3
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Explanation: If 185 calories=2 miles then 1 mile=92.5 calories. 185+92.5=277.5
Answers
Answer:
B: 24ft^2
Step-by-step explanation:
Area of triangle = (base x height)/2
Step 1: form an equation
a = (12ft x 4ft)/2
Step 2: solve equation
a = 48ft^2 / 2
a = 24ft^2
*the base is the measurement for the bottom of a triangle while height is the measurement of the length from the bottom to the top of a triangle*