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No. & Date Asked  Question 

# 913 :: 12/5/11

The mean is 112 oz, and the standard deviation is 40 oz. Compute the probability that the mean from a sample of 49 will fall between 103 and 121 oz. . .
ZScore,
Area between,
Standard Error of the Mean 
# 824 :: 11/8/09

The grades on a statistics midterm test are normally distributed with a mean of 78 and a standard deviation of 6
a. What proportion of the class has . . .
ZScore,
Standard Error of the Mean 
# 520 :: 11/23/08

Your company asks you to compare a new advertising campaign and the old one. Sample data on the accounts as follows:
Old: 40, 28, 35, 38, 31, 42, 26,. . .
Confidence Intervals,
Median,
Mode,
mean,
tstatistic,
Standard Error of the Mean 
# 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 
# 485 :: 10/27/08

Assume that the heights of 5 year old boys are normally distribued with a mean of 100cm and a standard deviation of 60. What is the sampling distribut. . .
TINV,
Confidence Intervals,
Standard Error of the Mean,
Standard Deviation of the Mean 
# 391 :: 9/18/08

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,
tstatistic,
Confidence Intervals,
Critical Value 
# 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 
# 151 :: 4/14/08

A random sample of 25 households finds that an average of 2.3 people reside in each house (the standard deviation is 0.35). With a 95% confidence lev. . .
TINV,
tstatistic,
tdistribution,
Confidence Intervals,
Standard Error of the Mean,
Margin of Error 