Question
In: Statistics and Probability
Suppose a new standardized test is given to 100 randomly selected third-grade students in Connecticut. The...
Suppose a new standardized test is given to 100 randomly selected third-grade students in Connecticut. The sample average score x¯ on the test is 58 points, and the sample standard deviation, sx, is 8 points.
2.1 The authors pan to administer the test to all third-grade students in Connecticut. Construct 95% confidence interval for the mean score on all Connecticut third graders. (5 points)
2.2 Suppose the same test is given to a 200 randomly selected third graders from Iowa, producing a sample average of 62 points and sample standard deviation of 11 points. Construct a 90% confidence interval for the difference in mean scores between Connecticut and Iowa. (10 points)
2.3 Can you conclude with a high degree of confidence that the population means for Iowa and Connecticut students are difference? (10 points)
Solutions
orchestra answered 2 years agoRelated Solutions
Suppose a new standardized test is given to 97 randomly selected third-grade students in New Jersey....
Suppose a new standardized test is given to 97 randomly
selected third-grade students in New Jersey. The sample average
score Upper Y overbarY
on the test is 56 points and the sample standard deviation, s
Subscript Upper YsY, is 10 points. The authors plan to
administer the test to all third-grade students in New Jersey.
1. The 95% confidence interval for the mean score of all New
Jersey third graders is (round to two decimal places).
2. Suppose the same...
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The grade averages for 10 randomly selected junior college
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80 83 48 76 72 94 75 91 65
In a school district, all sixth grade students take the same standardized test. The superintendant of...
In a school district,
all sixth grade students take the same standardized test. The
superintendant of the school district takes a random sample of 2323
scores from all of the students who took the test. She sees that
the mean score is 147147 with a standard deviation of
18.963118.9631. The superintendant wants to know if the standard
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standard deviation was 1212. Is there evidence that the standard
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In a school district, all sixth grade students take the same
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In a school district, all sixth grade students take the same standardized test. The superintendant of...
In a school district, all sixth grade students take the same
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of 28.2396. The superintendant wants to know if the standard
deviation has changed this year. Previously, the population
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In a school district, all sixth grade students take the same standardized test. The superintendent of...
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In a school district, all sixth grade students take the same standardized test. The superintendant of...
In a school district, all sixth grade students take the same
standardized test. The superintendant of the school district takes
a random sample of 26 scores from all of the students who took the
test. She sees that the mean score is 101 with a standard deviation
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deviation has changed this year. Previously, the population
standard deviation was 21. Is there evidence that the standard
deviation of test scores has...
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