statistics

Reading placement scores for a particular college are normally distributed with a mean of 72 and a standard deviation of 7.

a) draw a sketch of the reading placement scores for students at this college. be sure to mark the mean and also to mark one and two standard deviations from each side of the mean.

b) 95% of students at this college have a reading placement score between ______ and ______

c) Sammy's reading placement score is 82. What is his z-score?

d) Find the proportion of students at this college who have a reading placement score of at least 82.

e) Elisa's z-score is -1.5. What is her reading placement score?

f) How high does one's reading placement score have to be so that a student is in the 85th percentile?

1. 👍 0
2. 👎 0
3. 👁 127
1. a. http://en.wikipedia.org/wiki/Standard_deviation

b. 95% = mean ± 1.96 SD

c. Z = (score-mean)/SD

d. Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion from the Z score, using equation above.

e. Use same equation.

f. Use same table to find Z score and calculate.

1. 👍 0
2. 👎 0
posted by PsyDAG

Similar Questions

1. probability

The National Center for Educational Statistics reported that in 2009 the ACT college placement and admission examination were normally distributed and had a mean of 21.1 and standard deviation of 5.1. A college requires applicants

asked by matt on September 21, 2015
2. statistics

for randomly selected adults, IQ scores are normally distributed with a standard deviation of 15. the scores of 14 randomly selected college students are listed below. use a 0.10 significance level to test the claim that the

asked by Juan on April 29, 2019
3. stat

for randomly selected adults, IQ scores are normally distributed with a standard deviation of 15. the scores of 14 randomly selected college students are listed below. use a 0.10 significance level to test the claim that the

asked by carl on May 14, 2012
4. statistics

Scores on the ACT college entrance exam are Normally distributed with a mean µ = 20 and standard deviation σ = 5. An SRS of 25 ACT scores is selected, construct a 95% Confidence Interval for the sample mean (X-Bar) and interpret

asked by Alyssa on December 3, 2012
5. Derrick

John kept track of all his math and reading test scores throughout the year as shown in the table below. Test 1:90math 80reading Test 2:75math 90reading Test 3:80math 70reading Test 4:90math 75reading Test 5:95math 90reading What

asked by running.from.myself on March 19, 2012
6. Statistics

Each year, thousands of college seniors take the Graduate Record Examination (GRE). Assume the scores are transformed so they have a mean of 600 and a standard deviation of 150. Furthermore, the scores are known to be normally

asked by Emily on October 8, 2011
7. Probability and Statistics

The ACT scores of applicants to college are approximately normally distributed with a mean of 20.3 and a standard deviation of 3.1. If a random sample of 20 applicants to college is chosen find the probability that their average

asked by Kim on April 29, 2012
8. math

Reading readiness of preschoolers from an impoverished neighborhood (n = 20) was measured using a standardized test. Nationally, the mean on this test for preschoolers is 30.9, with s = 2.08. a.Children below the 30th percentile

asked by Elizabeth on September 3, 2010
9. statisitcs

The combined math and verbal scores for students taking a national standardized examination for college admission is normally distributed with a mean of 560 and a standard deviation of 180. If a college requires a student to be in

asked by veronica on October 23, 2014
10. Math

The combined math and verbal scores for students taking a national standardized examination for college admission, is normally distributed with a mean of 620 and a standard deviation of 220. If a college requires a student to be

asked by Ashley on February 9, 2014

More Similar Questions