T-Test Statistic Problems
Question)
Creative Good, a New York consulting firm, claimed that 39% of shoppers fail in their
attempt to purchase merchandise on-line because Web sites are too complex. A r
Standard Deviation Problems
Question)
If standards deviation is 6 what is the sum of squares?
Answer)
Standard Deviation = Sqrt( Variance)
Variance we know that = Sum(Xi)^2 [Sum(Xi)]^2/ n
S.D=6
Varian
Pooled Variance Problems
Question)
Calculate the Pooled Variance for the following sample data & Test the Hypothesis.
Once using the pooled variance calculated above and the second time using assumpti
Normal Distribution Problems
Question)
If the mean is 60 and the standard deviation is 9 and 79 subjects completed the test.
a) How many sores will fall above 70?
b) Between 56 and 72?
c) Between 50 a
Normal Distribution Problems
Question)
A melting point test of n=10 samples of a binder used in manufacturing a rocket propellant
resulted in average of 154.2 F
Assume that melting point is normally d
Margin of Error Problems
Question)
A national safety council wishes to estimate the proportion of automobile accidents that
involve pedestrians. How large a random sample of accident records must be e
Hypothesis Test Problems
Question)
A recent broadast of televison show had a 10 share, meaning that among 6000 monitored
households with TV sets in use 10% of them were tuned to this program. Use a 0.
Distribution Problems Stats
The administration of Whatsamatta University wishes to determine if the mean credit card
debt of its
Students exceed the national average of $2200. A survey of 50 students
Correlation Co-efficient with t-test Statistic
Question)
If n = 15 and r = .4296, the corresponding t-statistic to test for zero correlation is what?
Answer)
Formula for calculating t-test statistic w
Confidence Interval Problems-Question)
Suppose that the same firm develops a new light bulb, with the goal of producing a light bulb
with a longer lifetime at the same cost. If 100 of the new bulbs ar
Confidence Interval Problems
Question)
For several years researchers have noticed that there appears to be a regular, year-to-year
Increase in the average IQ for the general population. This phenomeno
Confidencce Interval Problems.
Question)
A survey shows that a family of 3 spends on average about $3500 on
a vacation. The survey was conducted on 200 families. Assuming a
standard deviation of $450,
Question)
Calculate the unknowns for the following situations based on the given data.
Actual total sales revenue $400,000
Total fixed cost $75,000
Unit variable cost $15
Contribution margin ratio 40%