Statistics Test 1 Prof. VanderHoff Spring 2004
All work must be shown on exam
to receive credit.
1. [20] Calculate
the statistics below using the following data from a sample:
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9 |
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-1 |
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4 |
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3 |
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7 |
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9 |
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3 |
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2 |
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-1 |
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5 |
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Mean:
Median
Mode
Range
Variance
Standard deviation
2. [8] Calculate
the grade point average using the following data:
Grade credits
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3. [5] The
average time it takes to get lunch is 18 minutes and the standard deviation is 4
minutes. About 95% of lunches take between
___________ and _____________.
4. [5] The
probability that A occurs is .5. The
probability that B occurs is .3. The
probability that A and B occur is .1.
Are A and B independent? Show your work.
5. [7] There
are 30 women and 20 men is a class. If 10
people are chosen, what is the probability that there will be 4 men and 2 woman?
6 [5] The ACC conference has 9
teams. How many different ways can the 3
top teams finish?
7. [15] calculate the statistics below using the following data from a sample:
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Y |
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4 |
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7 |
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2 |
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9 |
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9 |
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4 |
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5 |
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8 |
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3 |
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1 |
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1 |
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1 |
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Covariance of X and Y
Correlation coefficient of X
and Y
Is X or Y more variable?
8. [5]. A cooler has 5 Cokes,
10 Pepsis and 10 Beers. If you pick two
drinks at random, what is the probability you will get no beer [0 beers]?
9. [5] The
probability on ice is .3; the probability of sun is .4. Sun and ice are mutually exclusive. What is the probability of ice or sun?
10. [5] The
probability the a question is answered correctly is 2/3. What is the probability that
3 of the 4 questions are answered
correctly?
11. [5] The
probability it rains any given day is .1.
What’s the probability it rains more than 4 days in the next 20 days?
12. [5] The
mean number of burgers served per hour is 20.
What is the probability that more than 35 will be served?
13. [10] Calculate
the expected value of X and the standard deviation of X:
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