 Showing of 26 Questions
# 899 :: 9/5/11 In a study , the average age of the male candidates who were affected , was 38.20 whereas the average age of the female subjects was calculated to 34. . .
# 843 :: 2/27/10 Braking distances of cars. A random sample of 13 four-cylinder cars is obtained and braking distances are measured and found to have a mean of 137.5 . . .
# 820 :: 10/17/09 An animal trainer obtained the following sample data (Table A) in a study of reaction times of dogs (in seconds) to a specific stimulus. He then selec. . .
# 691 :: 4/21/09 Calculate the Standard Deviation of the following list of data: 6, 7, 8, 9, 10. . .
# 677 :: 4/17/09 A random sample of 51 observations was selected from a normally distributed population. The sample mean was x = 88.6 , and the sample variance was s2 . . .
# 540 :: 12/9/08 A sample of 36 observations is selected from a normal population. The sample mean is 21, and the sample standard deviation is 5. Conduct the following. . .
# 512 :: 11/14/08 When estimating the mean of a population, how large must the sample be in order that the 95% error margin is 1/8 the standard deviation?. . .
# 475 :: 10/12/08 A telephone manufacturer wants its telescope to have standard deviation in resolution to be significantly below 2 when focusing on object 500 light-ye. . .
# 470 :: 10/9/08 A telescope manufacturer wants its telescopes to have standard deviations in resolution to be significantly below 2 when focusing on objects 500 light. . .
# 403 :: 9/22/08 Based on information obtained from a sample of 54, a 98% confidence interval for the average profit level of regional banks is given by 67.4 million t. . .
# 377 :: 9/10/08 A sample of households that subscribe to the United Bell Phone Company revealed the following numbers of calls received by each household last week. D. . .
# 344 :: 8/14/08 Explain the difference between testing a single mean and testing the difference between two means. What two assumptions must be met when one is using . . .
# 335 :: 8/10/08 The random variable x has the following probability distribution. x 1 2 3 4 5 P(x) 0.5 0.2 0.1 0.1 0.1 Find the mea. . .
# 327 :: 8/8/08 Want a sample size of about 60 (30 controls and 30 cases). At 5% significance and 80% power.How do i determine the standard deviation and mean differe. . .
# 315 :: 8/5/08 An engineer in an automotive factory wishes to know what the tire pressure is on all cars leaving the factory. She measures the tire pressure on a sa. . .
# 230 :: 6/11/08 a score that is 8 points above the mean corresponds to a z-score=0.05 What is the population standard deviation?. . .
# 215 :: 6/3/08 Annual starting salaries for college graduates with degrees in business administration are generally expected to be between \$30,000 and \$45,000. Assum. . .
# 197 :: 5/15/08 Annual starting salaries for college graduates with degrees in business administration are generally expected to be between \$30,000 and \$45,000. Assum. . .
# 181 :: 5/5/08 What is the difference between a population standard deviation and a sample standard deviation?. . .
# 167 :: 4/24/08 I know that 33 is the raw score of the 85th percentile. How do I determine the mean?. . .
# 163 :: 4/22/08 When calculating confidence interval estimates...how is the x and standard deviation calculated?. . .
# 155 :: 4/16/08 difference between a sample parameter ( X-bar and s ) and a proportion parameter ( p )? . . .
# 37 :: 10/29/07 How do you calculate the z score for the raw score of 10 based on the following distribution: 8, 9, 15, 30, 7, 8 ?. . .
# 21 :: 10/29/07 How do you calculate standard deviation?. . .
# 14 :: 10/23/07 What percent of the time should this occur? (Z-Score) ?. . .
# 6 :: 10/23/07 How do you determine the sample size for data for which the mean and standard deviation are not known?. . .