Question
Sample Size for 90% CL, E = 2.1 and σ = 19
Sample Size for 90% CL, E = 2.1 and σ = 19
Homework Answers
Answer #1
Solution :
Given that,
standard deviation = 
= 19
margin of error = E = 2.1
At 90% confidence level the z is ,
= 1 - 90% = 1 - 0.90 = 0.10
/ 2 = 0.10 / 2 = 0.05
Z/2
= Z0.05 = 1.645
Sample size = n = ((Z/2
*
) / E)2
= ((1.645 * 19) / 2.1)2
= 221.51 = 222
Sample size = 222
Not the answer you're looking for?
Similar Questions
Determine the sample size for the estimate of for the following. E = 5.55 , σ...
Determine the sample size for the estimate of for the following.
E = 5.55 , σ = 18.22 , confidence level = 90 % . Round your answer
up to the nearest whole number.
Determine the sample size necessary under the following conditions. a. To estimate μ with σ =...
Determine the sample size necessary under the following
conditions.
a. To estimate μ with σ = 44, E = 3,
and 95% confidence
b. To estimate μ with a range of values from 20
to 88 with E = 2 and 90% confidence
c. To estimate p with p
unknown, E = .04, and 98% confidence
d. To estimate p with E =
.03, 95% confidence, and p thought to be approximately
.70
When σ is unknown and the sample is of size n ≥ 30, there are two...
When σ is unknown and the sample is of size n
≥ 30, there are two methods for computing confidence intervals for
μ.
Method 1: Use the Student's t distribution with
d.f. = n − 1.
This is the method used in the text. It is widely employed in
statistical studies. Also, most statistical software packages use
this method.
Method 2: When n ≥ 30, use the sample standard
deviation s as an estimate for σ, and then use
the...
Suppose x has a distribution with μ = 19 and σ = 15. (a) If a...
Suppose x has a distribution with μ = 19 and σ = 15. (a) If a
random sample of size n = 48 is drawn, find μx, σ x and P(19 ≤ x ≤
21). (Round σx to two decimal places and the probability to four
decimal places.) μx = σ x = P(19 ≤ x ≤ 21) = (b) If a random sample
of size n = 58 is drawn, find μx, σ x and P(19 ≤ x ≤...
When σ is unknown and the sample is of size n ≥ 30, there are two...
When σ is unknown and the sample is of size n
≥ 30, there are two methods for computing confidence intervals for
μ.
Method 1: Use the Student's t distribution with
d.f. = n − 1.
This is the method used in the text. It is widely employed in
statistical studies. Also, most statistical software packages use
this method.
Method 2: When n ≥ 30, use the sample standard
deviation s as an estimate for σ, and then use
the...
A population has mean μ = 19 and standard deviation σ = 5. A random sample...
A population has mean μ = 19 and standard deviation σ = 5. A
random sample of size n = 64 is selected. What is the probability
that the sample mean is less than 18?
When σ is unknown and the sample is of size n ≥ 30, there are two...
When σ is unknown and the sample is of size n ≥ 30, there are
two methods for computing confidence intervals for μ. Method 1: Use
the Student's t distribution with d.f. = n − 1. This is the method
used in the text. It is widely employed in statistical studies.
Also, most statistical software packages use this method. Method 2:
When n ≥ 30, use the sample standard deviation s as an estimate for
σ, and then use the...
Is there a minimum sample size that must be used? What is the minimum sample size?...
Is there a minimum sample size that must be used? What is the
minimum sample size? What might be an advantage to collecting a
sample larger than the minimum sample size?
p = .4028 n= 72 cl= .95 E= .11329
A simple random sample of size n =19 is drawn from a population that is normally...
A simple random sample of size n =19 is drawn from a population
that is normally distributed with σ=16. The sample mean is found to
be x overbar = 65. Construct a 95% confidence interval about the
population mean.
a.) Given a normal distribution with σ = 0.380. Find the required sample size for a...
a.) Given a normal distribution with σ = 0.380. Find the
required sample size for a 95% confidence level (estimating the
mean), given a margin-of-error of 6%.
b.) Given the sample results taken from a normal population
distribution: mean = 4.65, σ = 0.32, and n = 17.
For a 99% confidence interval, find the margin-of-error for the
population mean. (use 2 decimal places)
c.) Given the sample results taken from a normal population
distribution: mean = 1.25, σ =...
ADVERTISEMENT
Need Online Homework Help?
Get Answers For Free
Most questions answered within 1 hours.
ADVERTISEMENT
Active Questions
asked 35 minutes ago
asked 40 minutes ago
asked 40 minutes ago
asked 47 minutes ago
asked 48 minutes ago
asked 49 minutes ago
asked 56 minutes ago
asked 1 hour ago
asked 1 hour ago
asked 1 hour ago
asked 1 hour ago
asked 1 hour ago