Question

In state A, 19% of the people drink coffee. In state B, 27% of the people drink coffee.

We take a random sample of 50 from state A, and 60 from state B, and find the sample proportions spA and spB (spA is the sample proportion of those who drink coffee from state A, which in the notation of the textbook would be )

What is the standard deviation of spA? (write it as a decimal fraction, not a percentage; provide three decimal places)

Answer #1

Solution

Given that,

sample proportion = _{
} = 0.19 ( spA )

= 1 - _{
} = 1 - 0.19 = 0.81

sample proportion = _{
} = 0.27 ( spB )

n = 50 ( spA )

n = 60 ( spB )

_{}
= [_{}(
1 - _{
} ) / n] =
[(0.19 * 0.81) / 50 ] = 0.055 ( spA )

1.
In state A, 23% of the people drink coffee. In state B, 37% of
the people drink coffee.
We take a random sample of 50 from state A, and 60 from state B,
and find the sample proportions spA and spB (spA is the sample
proportion of those who drink coffee from state A, which in the
notation of the textbook would be p1)
What is the mean of spA - spB? (write it as a decimal fraction,
not...

Hypothesis Test Example For Proportions:
What proportion of people do not drink alcohol? You believe that
the proportion of people in the U.S.A. who do not drink is less
than 15%. To determine if you are correct, you take a SRS of 400
U.S. residents, and find the proportion of people who do not drink
in your sample is 0.22. Conduct a hypothesis test at the 5%
significance level.
A). Write the hypotheses for the test.
B). Check the assumptions...

It has been reported that 48% of people text and drive. A random
sample of 60 drivers is drawn. Find the probability that the
proportion of people in the sample who text and drive is less than
0.493 . Write only a number as your answer. Round to 4 decimal
places (for example 0.3748). Do not write as a percentage.

More and more people are buying store brand products rather than
national brand products. A coffee company claims that 40% of their
customers buy national brand coffee. A random sample of 700 people
who buy coffee showed that 259 of them buy national brand coffee.
Use a 1% level of significance to test the percentage of people who
buy national brand coffee is different from 40%

Your 300 mL cup of coffee is too hot to drink when served at
90°C. An ice cube, taken from a −20°C freezer is used to cool your
coffee to a pleasant 60°C. Assume that you have a well-insulated
cup.
a. Provide the statement of energy conservation for this closed
“coffee-ice” system.
b. What is the heat lost by coffee in bringing down the
temperature to 60°C?
c. How much heat is consumed in converting ice to water at 0°C?...

McBeans magazine recently published a news article about
caffeine consumption in universities that claims that 80% of people
at universities drink coffee regularly. Moonbucks, a popular coffee
chain, is interested in opening a new store on UBC campus. After
reading McBeans' article, they will consider opening a store in UBC
if more than 80% of the people in UBC drink coffee regularly. A
random sample of people from UBC was taken, and it was found that
680 out of 810...

27)
The mean salary of people living in a certain city is $37,500
with a standard deviation of $1,614. A sample of 49 people is
selected at random from those living in the city.
Find the probability that the mean income of the sample is less
than $38,000.
Round your answer to 4 decimal places.
Please explain each step in detail.

27)
The mean salary of people living in a certain city is $37,500
with a standard deviation of $1,614. A sample of 49 people is
selected at random from those living in the city.
Find the probability that the mean income of the sample is less
than $38,000.
Round your answer to 4 decimal places.
Please show all steps and explain in detail. Thank you!

Survey 40 people and ask them this question: “What is your
favorite soft drink?” You record your results and realize that 10
of those people chose Dr. Pepper. You calculated your sample
proportion for the 10 individuals who chose Dr. Pepper, and
standard error. The following are your results:
Proportion: 0.25
Standard Error: 0.0684
You then ask a friend what percentage of people do you think
would say that Dr. Pepper is their favorite soft drink? You friend
claims that...

2.- Of the 40,000 people who are constructing a building in the
state of California, a random sample of 522 was seen and their
daily income was investigated. The following table shows the
results.
Income X
Number of People
50 to less than 60
75
60 to less than 70
97
70 to less than 80
135
80 to less than 90
155
90 to less than 100
60
Total
522
Construct a 90% confidence interval for the daily income...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 12 minutes ago

asked 24 minutes ago

asked 34 minutes ago

asked 47 minutes ago

asked 52 minutes ago

asked 59 minutes ago

asked 59 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago