Determine the minimum sample size required when you want to be 80% confident that
the sample mean is within 1.5 units of the population mean. Assume a standard
deviation of 9.24 in a normally distributed population. - ✔✔63
Determine the minimum sample size required when you want to be 75% confident that
the sample mean is within thirty units of the population mean. Assume a standard
deviation of 327.8 in a normally distributed population - ✔✔158
In a sample of 8 high school students, they spent an average of 28.8 hours each week
doing sports with a standard deviation of 3.2 hours. Find the 95% confidence interval. -
✔✔(26.12, 31.48)
In a sample of 15 stuffed animals, you find that they weigh an average of 8.56 ounces
with a standard deviation of 0.08 ounces. Find the 92% confidence interval. -
✔✔(8.521, 8.599)
Market research indicates that a new product has the potential to make the company
an additional $3.8 million, with a standard deviation of $1.7 million. If this estimate was
based on a sample of 10 customers, what would be the 90% confidence interval? -
✔✔(2.81, 4.79)
A heated election is coming up where people will select the all-time favorite cartoon.
We take a poll before the election to see how the race is shaping up. According to this
poll, 34% of the people say they will vote for Bugs Bunny and 26% say they will vote for
Baby Shark. The poll has an error of +/-2 %. Based on this result, can one say that in the
population, more people clearly support Bugs Bunny over Baby Shark? - ✔✔Yes, as
the confidence intervals for the two groups do not overlap
, In a sample of 17 small candles, the weight is found to be 3.72 ounces with a standard
deviation of 0.963 ounces. What would be the 87% confidence interval for the size of
the candles? - ✔✔(3.347, 4.093)
In a situation where the standard deviation was decreased from 5.8 to 3.1, what would
be the impact on the confidence interval? - ✔✔It would become narrower due to the
change in standard deviation
In a random sample of eighteen people, the mean time at lunch was 28.4 minutes with a
standard deviation of 8.2 minutes. Assuming the data are normally distributed, what
would be the 85% confidence interval? - ✔✔(25.49, 31.31)
If a confidence interval is known to be (56.28, 62.72), what would be its margin of error?
- ✔✔3.22
A company manufacturers soda cans with a diameter of 52 millimeters. In a sample of
12 cans, the standard deviation was 2.3 millimeters. What would be the 96% confidence
interval for these cans? - ✔✔(50.45, 53.55)
From a random sample of 68 businesses, it is found that the mean time that employees
spend on personal issues each week is 4.9 hours with a standard deviation of 0.35
hours. What is the 95% confidence interval for the amount of time spent on personal
issues? - ✔✔(4.82, 4.98)
If the population standard deviation of a sample decreases without other changes, what
is most likely to happen to the confidence interval? - ✔✔narrows
From a random sample of 41 teens, it is found that on average they spend 31.8 hours
each week online with a population standard deviation of 3.65 hours. What is the 90%
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Examsplug. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.49. You're not tied to anything after your purchase.