Solution:
Given that,
P(-z < Z < z) = 25%
P(-z < Z < z) = 0.25
P(Z < z) - P(Z < z) = 0.25
2P(Z < z) - 1 = 0.25
2P(Z < z) = 1 + 0.25
2P(Z < z) = 1.25
P(Z < z) = 1.25 / 2 = 0.625
P(Z < 0.3186) = 0.625
z = 0.32
z = - 0.32
13.) What IQ interval captures the middle 25% of the population (n-1)?
If X = 100,0=13, and n=65, construct a 95% confidence interval estimate of the population mean, . (Round to two decimal places as needed)
(1 point) Use the given data to find the 95% confidence interval estimate of the population mean p. Assume that the population has a normal distribution IQ scores of professional athletes: Sample size n = 30 Mean 2 = 104 Standard deviation s = 10
Determine the margin of error for a confidence interval to estimate the population mean with n=25 and s =1.6 for the confidence levels below. a) 80% b) 90% c) 99% a) The margin of error for an 80% confidence interval is. (Round to two decimal places as needed.) b) The margin of error for a 90% confidence interval is. (Round to two decimal places as needed.) c) The margin of error for a 99% confidence interval is. (Round to two...
A 95% confidence interval for a population mean goes from 10 to 13. The interval was based on a sample size of 45. The interval was calculated using a known population standard deviation but the value has been lost. What is the population standard deviation?
Assume population mean IQ is 100 standard deviation 12 sample of 25 students and average score was 108 If another sample of 25 students was selected, what is the probability that the sample would have a mean greater than 108?
Construct a 95% confidence interval to estimate the population mean using the following data: x̅=38,s=8.5, n=25 (show work) Margin of error=_______ Confidence interval=_______ What assumption (if any) did you have to make to construct this interval? ______
Use the given data to find the 95% confidence interval estimate of the population mean μμ. Assume that the population has a normal distribution. Give your answers to 2 decimal places. IQ scores of professional athletes: Sample size n=25n=25 Mean x¯¯¯=105x¯=105 Standard deviation s=15s=15 equation editor <μ<<μ< equation editor
A thermal radiation detector captures wavelengths within an interval Δλ = 2.0 nm . What is the total intensity measured by the detector at a center wavelength of 0λ = 800 nm from an object heated to 2500K. (Hint: you may estimate this answer without doing an integral.)
Descriptive Statistics Table 13 N Range Minimum Maximum Mean Std. Deviation Variance IQ 20 25 15 40 26.85 7.700 59.292 Driving Test Score 20 18 2 20 10.45 5.453 29.734 age 20 6 19 25 21.05 1.820 3.313 Valid N (listwise) 20 Please show work so that I can follow along 13. Discuss what Table 13 indicates. (10 points)
A random sample of n = 25 observations is taken from a N(µ, σ ) population. A 95% confidence interval for µ was calculated to be (42.16, 57.84). The researcher feels that this interval is too wide. You want to reduce the interval to a width at most 12 units. a) For a confidence level of 95%, calculate the smallest sample size needed. b) For a sample size fixed at n = 25, calculate the largest confidence level 100(1 −...