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No. & Date Asked  Question 

# 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. . .
Variance,
Standard Deviation 
# 843 :: 2/27/10

Braking distances of cars. A random sample of 13 fourcylinder cars is obtained and braking distances are measured and found to have a mean of 137.5 . . .
Standard Deviation,
Two Variances,
Fstatistic 
# 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. . .
Standard Deviation,
Standard Deviation on Frequency Data,
Standard Deviation of Grouped Data,
Ftest 
# 691 :: 4/21/09

Calculate the Standard Deviation of the following list of data: 6, 7, 8, 9, 10. . .
Standard Deviation 
# 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 . . .
ChiSquare,
Standard Deviation,
Population Standard Deviation,
sample variance,
sampe standard deviation 
# 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. . .
1sample ttest,
1tailed test,
Null Hypothesis ,
calculating mean,
sample variance,
Standard Deviation 
# 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?. . .
Sample Size,
Margin of Error,
Standard Deviation,
Standard Error of the Mean 
# 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 lightye. . .
Standard Deviation,
ChiSquare,
ChiSquare Distribution 
# 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. . .
ChiSquare Distribution,
Confidence Intervals,
Standard Deviation,
Variance 
# 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. . .
Standard Deviation,
Margin of Error,
Critical Value,
Confidence Intervals,
Confidence Level 
# 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. . .
mean,
Median,
Standard Deviation 
# 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 . . .
Standard Deviation,
ztest,
Normally Distributed,
Homogeneity of Variance 
# 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. . .
Expected Value,
Random Variable,
Standard Deviation 
# 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. . .
Power,
Standard Deviation,
Mean Difference 
# 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. . .
Standard Error of the Mean,
Standard Deviation,
Confidence Intervals,
Critical Value,
tstatistic 
# 230 :: 6/11/08

a score that is 8 points above the mean corresponds to a zscore=0.05 What is the population standard deviation?. . .
Standard Deviation,
ZScore 
# 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. . .
Standard Normal Curve,
Confidence Intervals,
Standard Deviation,
Normally Distributed 
# 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. . .
Normally Distributed,
Standard Deviation,
Margin of Error,
Sample Size 
# 181 :: 5/5/08

What is the difference between a population standard deviation and a sample standard deviation?. . .
Standard Deviation,
Degrees of Freedom 
# 167 :: 4/24/08

I know that 33 is the raw score of the 85th percentile. How do I determine the mean?. . .
Percentile,
Standard Deviation 
# 163 :: 4/22/08

When calculating confidence interval estimates...how is the x and standard deviation calculated?. . .
Standard Deviation,
Confidence Intervals 
# 155 :: 4/16/08

difference between a sample parameter ( Xbar and s ) and a proportion parameter ( p )?
. . .
xbar,
Standard Deviation 
# 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 ?. . .
ZScore,
Standard Deviation 
# 21 :: 10/29/07

How do you calculate standard deviation?. . .
Standard Deviation 
# 14 :: 10/23/07

What percent of the time should this occur? (ZScore) ?. . .
ZScore,
Normally Distributed,
Standard Deviation,
Normal Curve 
# 6 :: 10/23/07

How do you determine the sample size for data for which the mean and standard deviation are not known?. . .
Standard Deviation,
Sample Size,
Margin of Error 