Question

QUESTION 1:

We want to estimate the mean change in score *µ* in the
population of all high school seniors. An SRS of 430 high school
seniors gained an average of x¯¯¯x¯ = 22 points in their
second attempt at the SAT Mathematics exam. Assume that the change
in score has a Normal distribution with standard deviation
48.114.

Find σx¯¯¯σx¯, the standard deviation of the mean change x¯¯¯x¯. (±±0.001).

Using the 68-95-99.7 Rule (Empirical Rule), give a 99.7% confidence interval for μμ based on this sample.

Confidence interval (±±0.001) is between and

QUESTION 2:

A class survey in a large class for first-year college students asked, "About how many hours do you study in a typical week?". The mean response of the 431 students was x¯¯¯x¯ = 17 hours. Suppose that we know that the study time follows a Normal distribution with standard deviation 7 hours in the population of all first-year students at this university.

What is the 99% confidence interval (±±0.001) for the population mean?

Confidence interval is from to hours.

Answer #1

The National Assessment of Educational Progress (NAEP) gave a
test of basic arithmetic and the ability to apply it in everyday
life to a sample of 840 men 21 to 25 years of age. Scores range
from 0 to 500; for example, someone with a score of 325 can
determine the price of a meal from a menu. The mean score for these
840 young men was x⎯⎯⎯x¯ = 272. We want to estimate the mean score
μμ in the...

ch16 #13. (16.19) A class survey in a large class for first-year
college students asked, "About how many hours do you study in a
typical week?". The mean response of the 462 students was x⎯⎯hat =
14 hours. Suppose that we know that the study time follows a Normal
distribution with standard deviation 8 hours in the population of
all first-year students at this university.
What is the 99% confidence interval (±±0.001) for the population
mean?
Confidence interval is from...

An SRS of 16 Spokane County Schools' seniors had a mean SAT
Verbal score of 500 with a standard deviation of s = 100. We know
that the population is normally distributed. We wish to determine a
90% confidence interval for the mean SAT Verbal score µ for the
population of all seniors in the district.
a. Using the above data, the critical value has how many degrees of
freedom?
b. What is the critical value for the 90% confidence...

To estimate the mean score μμ of those who took the Medical
College Admission Test on your campus, you will obtain the scores
of an SRS of students. From published information you know that the
scores are approximately Normal with standard deviation about 6.6.
You want your sample mean x⎯⎯⎯x¯ to estimate μμ with an error of no
more than 1 point in either direction.
(a) What standard deviation (±±0.0001) must x⎯⎯⎯x¯ have so that
99.7% of all samples give...

Assume that we want to estimate the mean IQ score for the
population of statistics students. How many statistics students
must be randomly selected for IQ tests if we want 95% confidence
that the sample mean is within 2 IQ points of the population mean?
Assume that σ = 15. Round the answer to the nearest large whole
number!

The mean test score for 48 male high school students is 23.6 and
the population standard deviation is 4.6
The mean test score for 58 female high school students is 20.6
and the population standard deviation is 4.2 At α=0.01,
can you reject the claim that male and female high school
students have equal test scores?

1.) Assume that a sample is used to estimate a population mean
μμ. Find the 95% confidence interval for a sample of size 700 with
a mean of 55.8 and a standard deviation of 14.1. Enter your answer
as a tri-linear inequality accurate to 4 decimal places.
< μ <
2.) Assume that a sample is used to estimate a population mean
μμ. Find the 99% confidence interval for a sample of size 69 with a
mean of 58.1 and...

A class survey in a large class for first-year college students
asked, "About how many hours do you study during a typical week?"
There were 464 responses to the class survey. Suppose that we know
that the study time follows a Normal distribution with standard
deviation
σ = 8.6
hours in the population of all first-year students at this
university.
One student claimed to study 10,000 hours per week (10,000 is more
than the number of hours in a year)....

You want to estimate the mean number of chocolate chips in
cookies. The average number of chocolate chips per cookie in a
sample of 40 cookies was 23.95, with a sample standard deviation of
2.55. (A) Find a 90% confidence interval for the mean number of
chocolate chips using the t-distribution. (B) Find a 90% confidence
interval for the mean number of chocolate chips using the standard
normal distribution (for this question, assume the population
standard deviation is equal to...

A survey of a group of students at a certain college, we call
College ABC, asked: "About how many hours do you study in a week?"
The mean response of the 400 students is 15.8 hours. Suppose that
the study time distribution of the population is known to be normal
with a standard deviation of 8.5 hours. Use the survey results to
construct a 95% confidence interval for the mean study time at the
College ABC. Show your work neatly.

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 1 minute ago

asked 18 minutes ago

asked 23 minutes ago

asked 25 minutes ago

asked 34 minutes ago

asked 41 minutes ago

asked 41 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago