Question

Consider a population (call it population 1) with mean 1 and standard deviation . Consider another...

Consider a population (call it population 1) with mean 1 and standard deviation . Consider another population (call it population 2) with mean 2 and standard deviation . A random sample of size 15 from population 1 resulted in a sample mean of 48. 9 and a standard deviation of 14. 6. Similarly a random sample of size 12 from population 2 resulted in a sample mean of 43. 2 and a standard deviation of 14. 4. Find the best possible estimate of the unknown population standard deviation .

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

the given data are:-

the best possible estimate of the unknown population standard deviation be:-

[ as we know that when, we do not know the population standard deviations, we estimate them using the two sample standard deviations using our independent samples, known as the standard error]

*** if you have any doubt regarding the problem please write it in the comment box.if you are satisfied please give me a LIKE if possible...

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
1. To estimate the mean of a population with unknown distribution shape and unknown standard deviation,...
1. To estimate the mean of a population with unknown distribution shape and unknown standard deviation, we take a random sample of size 64. The sample mean is 22.3 and the sample standard deviation is 8.8. If we wish to compute a 92% confidence interval for the population mean, what will be the t multiplier? (Hint: Use either a Probability Distribution Graph or the Calculator from Minitab.)
7. If I have a population of an unknown mean and unknown standard deviation, what is...
7. If I have a population of an unknown mean and unknown standard deviation, what is the 95% confidence interval estimate of the mean if a. A random sample of size 25 gives a mean of 50 and a standard deviation of 12 b. A random sample of size 16 gives a mean of 50 and a standard deviation of 12 8. The average cost per night of a hotel room in New York City is $325. Assume this estimate...
The mean of a population is 75 and the standard deviation is 14. The shape of...
The mean of a population is 75 and the standard deviation is 14. The shape of the population is unknown. Determine the probability of each of the following occurring from this population. a.A random sample of size 34 yielding a sample mean of 80 or more b.A random sample of size 120 yielding a sample mean of between 72 and 78 c.A random sample of size 220 yielding a sample mean of less than 75.3
The mean of a population is 76 and the standard deviation is 13. The shape of...
The mean of a population is 76 and the standard deviation is 13. The shape of the population is unknown. Determine the probability of each of the following occurring from this population. a. A random sample of size 36 yielding a sample mean of 78 or more b. A random sample of size 120 yielding a sample mean of between 75 and 79 c. A random sample of size 219 yielding a sample mean of less than 76.7 (Round all...
A simple random sample of 70 items resulted in a sample mean of 80. The population standard deviation is
A simple random sample of 70 items resulted in a sample mean of 80. The population standard deviation isσ = 15.(a)Compute the 95% confidence interval for the population mean. (Round your answers to two decimal places.)to(b)Assume that the same sample mean was obtained from a sample of 140 items. Provide a 95% confidence interval for the population mean. (Round your answers to two decimal places.)to(c)What is the effect of a larger sample size on the interval estimate?A larger sample size...
1. Consider a normally distributed population with a standard deviation of 64. If a random sample...
1. Consider a normally distributed population with a standard deviation of 64. If a random sample of 90 from the population produces a sample mean of 250, construct a 95% confidence interval for the true mean of the population. 2.A psychologist is studying learning in rats (to run a maze). She has a sample of 40 rats and their mean time to run the maze if 5 minutes with a standard deviation of 1. Estimate the average time to run...
A population has a mean of 400 and a standard deviation of 90. Suppose a sample...
A population has a mean of 400 and a standard deviation of 90. Suppose a sample of size 125 is selected and  is used to estimate . Use z-table. What is the probability that the sample mean will be within +/- 8 of the population mean (to 4 decimals)? (Round z value in intermediate calculations to 2 decimal places.)    What is the probability that the sample mean will be within +/- 14 of the population mean (to 4 decimals)? (Round...
A population has a mean of 200 and a standard deviation of 50. Suppose a simple...
A population has a mean of 200 and a standard deviation of 50. Suppose a simple random sample of size ̅ 100 is selected and ? is used to estimate ?. 1. What is the probability that the sample mean will be within ±5 of the population mean? 2. What is the probability that the sample mean will be within ±10 of the population mean?
Consider a population having a standard deviation equal to 9.94. We wish to estimate the mean...
Consider a population having a standard deviation equal to 9.94. We wish to estimate the mean of this population. (a) How large a random sample is needed to construct a 95% confidence interval for the mean of this population with a margin of error equal to 1? (Round your answer to the next whole number.) The random sample is             units. (b) Suppose that we now take a random sample of the size we have determined in part a. If we...
A simple random sample of 100 items from a population with a population standard deviation of...
A simple random sample of 100 items from a population with a population standard deviation of 9 resulted in a sample mean of 42. 1. Determine a 90% confidence interval for the population mean. 2. Determine a 95% confidence interval for the population mean. 3. What happened to the width of the confidence interval as the level of confidence increased from 90% to 95%?
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT