Westonci.ca is the best place to get answers to your questions, provided by a community of experienced and knowledgeable experts. Experience the convenience of finding accurate answers to your questions from knowledgeable professionals on our platform. Our platform provides a seamless experience for finding reliable answers from a network of experienced professionals.
Sagot :
Answer:
The minimum sample size required for the estimate is 345.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
The standard deviation is known to be 1.8.
This means that [tex]\sigma = 1.8[/tex]
What is the minimum sample size required for the estimate?
This is n for which M = 0.19. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.19 = 1.96\frac{1.8}{\sqrt{n}}[/tex]
[tex]0.19\sqrt{n} = 1.96*1.8[/tex]
[tex]\sqrt{n} = \frac{1.96*1.8}{0.19}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*1.8}{0.19})^2[/tex]
[tex]n = 344.8[/tex]
Rounding up to the next integer:
The minimum sample size required for the estimate is 345.
We hope you found what you were looking for. Feel free to revisit us for more answers and updated information. Thank you for your visit. We're dedicated to helping you find the information you need, whenever you need it. Get the answers you need at Westonci.ca. Stay informed with our latest expert advice.