Question

able legs made in your factory are unusable if their diameter is either too large or too small. The target diameter is 4 centimeters, with a known standard deviation of 0.3 centimeters. You take a sample of 5 table legs and find that their mean diameter is 4.2 centimeters. (Assume that the distribution is normal.)

For the following, round all answers to no fewer than 4 decimal places.

Write the null and alternative hypotheses to determine if the manufacturing process is working as expected. | |

H0:μ | Answer |

H1:μ | Answer |

Compute the test statistic: z= | Answer |

Find the corresponding p-value: P= | Answer |

Using α=0.025, has the mean size of table legs drifted significantly? |

Answer #1

This is the two tailed test .

The null and alternative hypothesis is

H_{0} :
= 4

H_{a} :
4

Test statistic = z

= ( - ) / / n

= (4.2 - 4) / 0.3 / 5

= 1.4907

Test statistic = 1.4907

P-value = 0.1360

P-value >

Fail to reject the null hypothesis .

has the mean size of table legs drifted significantly?
**No**

A mortgage specialist would like to analyze the average mortgage
rates for Atlanta, Georgia. He collects data on the annual
percentage rates (APR in %) for 30-year fixed loans as shown in the
following table. If he is willing to assume that these rates are
randomly drawn from a normally distributed population, can he
conclude that the mean mortgage rate for the population exceeds
4.2%? Test the hypothesis at the 10% level of significance. (You
may find it useful to...

The Toylot company makes an electric train with a motor that it
claims will draw an average of only 0.8 ampere (A) under a normal
load. A sample of nine motors was tested, and it was found that the
mean current was x = 1.32 A, with a sample standard
deviation of s = 0.44 A. Do the data indicate that the
Toylot claim of 0.8 A is too low? (Use a 1% level of
significance.)
What are we testing...

The Toylot company makes an electric train with a motor that it
claims will draw an average of no more than 0.8 amps under a normal
load. A sample of nine motors were tested, and it was found that
the mean current was x = 1.32 amps, with a sample standard
deviation of s = 0.43 amps. Perform a statistical test of the
Toylot claim. (Use a 1% level of significance.)
a.) What are we testing in this problem?
-single...

Let x be a random variable representing dividend yield of bank
stocks. We may assume that x has a normal distribution with σ =
2.5%. A random sample of 10 bank stocks gave the following yields
(in percents). 5.7 4.8 6.0 4.9 4.0 3.4 6.5 7.1 5.3 6.1 The sample
mean is x = 5.38%. Suppose that for the entire stock market, the
mean dividend yield is μ = 4.2%. Do these data indicate that the
dividend yield of all...

The Toylot company makes an electric train with a motor that it
claims will draw an average of no more than 0.8 amps under
a normal load. A sample of nine motors were tested, and it was
found that the mean current was x = 1.32 amps, with a
sample standard deviation of s = 0.41 amps. Perform a
statistical test of the Toylot claim. (Use a 1% level of
significance.)
A. What are we testing in this problem?
Option...

ASK YOUR TEACHER
question
Bill Alther is a zoologist who studies Anna's hummingbird
(Calypte anna). (Reference: Hummingbirds, K. Long, W.
Alther.) Suppose that in a remote part of the Grand Canyon, a
random sample of six of these birds was caught, weighed, and
released. The weights (in grams) were as follows.
3.7
2.9
3.8
4.2
4.8
3.1
The sample mean is = 3.75 grams. Let x be a
random variable representing weights of hummingbirds in this part
of the Grand Canyon....

A hospital reported that the normal death rate for patients with
extensive burns (more than 40% of skin area) has been significantly
reduced by the use of new fluid plasma compresses. Before the new
treatment, the mortality rate for extensive burn patients was about
60%. Using the new compresses, the hospital found that only 42 of
89 patients with extensive burns died. Use a 1% level of
significance to test the claim that the mortality rate has
dropped.
What are...

The Toylot company makes an electric train with a motor that it
claims will draw an average of only 0.8 ampere (A) under a normal
load. A sample of nine motors was tested, and it was found that the
mean current was x = 1.40 A, with a sample standard
deviation of s = 0.46 A. Do the data indicate that the
Toylot claim of 0.8 A is too low? (Use a 1% level of
significance.)
What are we testing...

1. Bill Alther is a zoologist who studies Anna's hummingbird
(Calypte anna). (Reference: Hummingbirds, K. Long, W. Alther.)
Suppose that in a remote part of the Grand Canyon, a random sample
of six of these birds was caught, weighed, and released. The
weights (in grams) were as follows. 3.7 2.9 3.8 4.2 4.8 3.1
The sample mean is = 3.75 grams. Let x be a random variable
representing weights of hummingbirds in this part of the Grand
Canyon. We assume...

Let x be a random variable that represents red blood cell count
(RBC) in millions of cells per cubic millimeter of whole blood.
Then x has a distribution that is approximately normal. For the
population of healthy female adults, suppose the mean of the x
distribution is about 4.68. Suppose that a female patient has taken
six laboratory blood tests over the past several months and that
the RBC count data sent to the patient's doctor are as follows. 4.9...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 1 minute ago

asked 2 minutes ago

asked 10 minutes ago

asked 20 minutes ago

asked 37 minutes ago

asked 43 minutes ago

asked 56 minutes ago

asked 58 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago