The population standard deviation (σ) is 2 for a standardized achievement test that is normally distributed. Calculate the standard error of the mean if you draw a random sample of 800 test scores. Show your work for full credit.
The population standard deviation (σ) is 2 for a standardized achievement test that is normally distributed....
Suppose scores of a standardized test are normally distributed and have a known population standard deviation of 8 points and an unknown population mean. A random sample of 25 scores is taken and gives a sample mean of 93 points. Find the margin of error for a confidence interval for the population mean with a 98% confidence level. z0.10 z0.05 z0.025 z0.01 z0.005 1.282 1.645 1.960 2.326 2.576 You may use a calculator or the common z values above. Round...
3. The scores in a standardized test are normally distributed with μ 100 and σ 15. (a) Find the percentage of scores that will fall below 112. (b) A random sample of 10 tests is taken. What is the probability that their mean scoretis below 1122
In the population, IQ scores are normally distributed with a mean of 100 and standard deviation of 15 a) in a random sample of 21 people, what is the probability of them having a mean IQ between 102 and 1057 Show.all work for full creditt b) Write a full sentence explaining the meaning of the probability you found in part (a)-include the context of the problem!
2a-b 2. A fifth grader takes a standardized achievement test (mean = 125, standard deviation = 15) and scores a 148 a. Draw and label a normal curve using the mean and standard deviation, b. What percent scored higher than the fifth grader?
Scores on a standardized test are normally distributed with a mean of 100 and a standard deviation of 20. If these scores are converted to standard normal Z scores, which of the following statements will be correct?
A standardized test's scores are normally distributed with a mean a 500 and a standard deviation of 100. If 1200 students take the test, how many would you expect to score over 650? Round your answer to the nearest whole number.
SHOW WORK! The scores on two standardized tests are normally distributed. The first test had a mean of 56 and a standard deviation of 6. The second test had a mean of 76 and a standard deviation of 6. What score would you need on the second test to equal a score of 70 on the first test? Give answer to the nearest whole number.
A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1466 and the standard deviation was 310. The test scores of four students selected at random are 1860 1200 2160 and 1360. Find the z-scores that correspond to each value and determine whether any of the values are unusual.
4. (10 points) The Graduate Record Examination (GRE) test scores x are normally distributed this year. The mean test score is 200 and the standard deviation is 10. Random test scores samples of size 30 are drawn. (a.) Calculate the mean and standard deviation of sampling distribution of sample means. Show all work. o mean = standard deviation = isiq Sabit to o lodowa (b.) Find the probability that the mean of a sample is less that 180. Show all...
Assume that IQ scores are normally distributed, with a standard deviation of 12 points and a mean of 100 points. If 50 people are chosen at random, what is the probability that the sample mean of IQ scores will not differ from the population mean by more than 2 points? (Round your answer to four decimal places.)