Question

A random sample of 15 size AA batteries for toys yield a mean of 2.68 hours with standard deviation, 1.24 hours.

(a) Find the critical value, t*, for a 99% CI. t* =

(b) Find the margin of error for a 99% CI.

Answer #1

Given that,

= 2.68

s =1.24

n = 15

Degrees of freedom = df = n - 1 = 15- 1 = 14

At 99% confidence level the t is ,

= 1 - 99% = 1 - 0.99 = 0.01

/ 2 = 0.01 / 2 = 0.005

_{t
/2 df} = t_{0.005,} 14=
**2.977** ( using student t table)

critical value =2.977

Margin of error = E = t_{/2,df}
* (s /n)

= **2.977*** ( 1.24/
15)

E=0.9531

Margin of error = E =0.9531

A random sample of 8 size AA batteries for toys yield a mean of
2.84 hours with standard deviation, 1.45 hours.
(a) Find the critical value, t*, for a 99% CI. t*
(b) Find the margin of error for a 99% CI

A random sample of 13 size AA batteries for toys yield a mean of
2.82 hours with standard deviation, 0.84 hours.
(a) Find the critical value, t*, for a 99% CI. t* =
(b) Find the margin of error for a 99% CI.

random sample of 19 size AA batteries for toys yield a mean of
3.45 hours with standard deviation, 1.23 hours.
(a) Find the critical value, ??, for a 99% CI. ?? =
(b) Find the margin of error for a 99% CI.

(1 point) A random sample of 20 size AA batteries for toys yield
a mean of 3.54 hours with standard deviation, 1.08 hours. (a) Find
the critical value, t*, for a 99% CI. t* = ______(b) Find the
margin of error for a 99% CI._____

A random sample of 14 size AA batteries for toys yield a mean of
3.23 hours with standard deviation, 0.54 hours. (a) Find the
critical value, t*, for a 99% CI (give to at least 3 decimal
places). t* =
(b) Find the margin of error for a 99% CI (give to at least 2
decimal places).

A random sample of 16 size AA batteries for toys yield a sample
mean of 2.72 hours with sample standard deviation 0.92 hours. Find
a 99% confidence interval for the mean hours of all AA
batteries.

6. Consumer report gave the following information about the life
(hour) size AA batteries in toys:, 3, 5, 7, 11, and 7,20(you need
to calculate mean and standard deviation first) a) Find mean and
Standard deviation b) Find 95% Confidence interval for life of the
batteries.

the mean life of a name brand aa battery is 19 hours. a consumer
group is interested in determining if generic aa batteries have a
shorter mean life. this group tested a random sample of 9 generic
AA batteries resulting in a mean life of 17.4 hours with a standard
deviation of 1.5 hours. you may assume that battery lives follow a
normal distribution. At 1% level of significance, do the generic AA
batteries have a mean life shorter than...

Power+, produces AA batteries used in remote-controlled toy
cars. The mean life of these batteries follows the normal
probability distribution with a mean of 18 hours and a standard
deviation of 5.4 hours. As a part of its testing program, Power+
tests samples of 25 batteries. Use Appendix B.1 for the
z-values.
a. What can you say about the shape of the
distribution of sample mean?
Shape of the distribution is
(Click to
select) Normal Uniform Binomial
b. What is the standard...

Power+, produces AA batteries used in remote-controlled toy
cars. The mean life of these batteries follows the normal
probability distribution with a mean of 22 hours and a standard
deviation of 5.6 hours. As a part of its testing program, Power+
tests samples of 25 batteries. Use Appendix B.1 for the
z-values.
a. What can you say about the shape of the
distribution of sample mean?
Shape of the distribution is
(Click to
select) Normal Uniform Binomial
b. What is the standard...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 6 minutes ago

asked 9 minutes ago

asked 12 minutes ago

asked 15 minutes ago

asked 15 minutes ago

asked 32 minutes ago

asked 34 minutes ago

asked 52 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago