SOLUTION: As the new city planner for a developing community you need to project a budget for garbage trucks. To support your numbers you will use an estimate of the mean weight of garbage
Algebra.Com
Question 275992: As the new city planner for a developing community you need to project a budget for garbage trucks. To support your numbers you will use an estimate of the mean weight of garbage discarded weekly by household.
a. Find the sample size necessary to estimate the mean if you want to be 90% confident that the sample mean is within 2 pounds of the true population mean. A sample of 62 households produced a standard deviation = 12.46 pounds
Try it again at a 95% and a 99% confidence and indicate the change in the sample size and why you think this is so.
b. Give an example from your workplace of a problem that requires you to determine a sample size.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
As the new city planner for a developing community you need to project a budget for garbage trucks. To support your numbers you will use an estimate of the mean weight of garbage discarded weekly by household.
a. Find the sample size necessary to estimate the mean if you want to be 90% confident that the sample mean is within 2 pounds of the true population mean. A sample of 62 households produced a standard deviation = 12.46 pounds
----
n = [z*s/E]^2
n = [invNorm(0.95]*(12.46/(sqrt(62))/2]^2
---
n = [1.96*24.92/sqrt(62)]^2
n = 38.48
Round up to n = 39
======================================
Try it again at a 95%
Change the z-value to invNorm(0.975)
---
and a 99% confidence
Change the z-value to invNorm(0.995)
-----
and indicate the change in the sample size and why you think this is so.
More confidence and sample size are directly related.
===========================================================
b. Give an example from your workplace of a problem that requires you to determine a sample size.
I'll leave that to you.
Cheers,
Stan H.
RELATED QUESTIONS
Imagine that you have just been elected the Mayor of Small City America. The City... (answered by stanbon)
Suppose you want to cover the backyard with decorative rock and plant some trees as the... (answered by Mathtut,jim_thompson5910)
Suppose you want to cover the backyard with decorative rock and plant some trees as the... (answered by jim_thompson5910)
Suppose you want to cover the backyard with decorative rock and plant some trees as the... (answered by stanbon)
b. For the first phase of the project, imagine you want to cover the backyard with... (answered by mananth)
b. For the first phase of the project, imagine you want to cover the backyard with... (answered by Theo)
Answer the following questions. Use Equation Editor to write mathematical expressions and (answered by solver91311)
Please Help:
The bilious mayor of Duckberg calls the mild mannered young city planner... (answered by ewatrrr)
Design a sampling method to obtain the individuals in the sample. Be sure to
support... (answered by Boreal)