SOLUTION: A standard placement test has a mean of 105 and a standard deviation of σ = 13. Determine the minimum sample size if we want to be 99% certain that we are within 3 points of t

Algebra.Com
Question 221022: A standard placement test has a mean of 105 and a standard deviation of σ = 13. Determine the minimum sample size if we want to be 99% certain that we are within 3 points of the true mean
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
A standard placement test has a mean of 105 and a standard deviation of σ = 13. Determine the minimum sample size if we want to be 99% certain that we are within 3 points of the true mean
--------------------------------------
n = [z*sig/E]^2
---
invNorm(0.005) = -2.576
n = [2.576*13/3]^2
---
n = 124.6
---
Round up to n= 125
================================

RELATED QUESTIONS

3. A standard placement test has a mean of 115 and a standard deviation of mean = 10.... (answered by stanbon)
A standard placement test has a mean of 115 and a standard deviation of  = 10.... (answered by stanbon)
A standard placement test has a mean of 115 and a standard deviation of  = 10.... (answered by stanbon)
A standard placement test has a mean of 115 and a standard deviation of 10. What is the... (answered by stanbon)
A normal population has μ = 30 and σ = 7. For a random sample of size n = 6,... (answered by ewatrrr)
2. The new Twinkle bulb has a standard deviation hours. A random sample of 77 light... (answered by stanbon)
15. A population has a mean μ = 90 and a standard deviation σ = 27. Find the... (answered by stanbon,ewatrrr)
A standard placement test has a mean of 125 and a standard deviation of 15. Determine the (answered by reviewermath)
A random sample of size 36 is to be selected A from a population that has a mean μ = (answered by ewatrrr)