Part I : Simple
Counting Place your answer in the
space provided.
___________ 1. ) If
there are three boys and four girls at a basketball game
together , how many ways can all three boys sit together ?
___________ 2. ) How
many different ways can we be dealt 5 cards of the same
suit from a standard 52 card deck ?
Part II :
Multiple Choice Place the correct
letter beside each question.
__________ 3. ) For a continuous distribution what is
the probability that x takes on a
specified value exactly ( P ( X = x)
) ?
A. ) 0
B. ) need the normal table first
C. ) 1
D. ) need to know the z - score
first
_________ 4. ) Which of the following is NOT a
valid statement of the probability of an event, A ?
A. ) P( A ) = 0 . 0
B. )
P ( A ) = 1 . 0
C. ) P ( A ) = 0 . 758473535
D. ) P ( A ) =
- 0 . 67
_________ 5. ) When
dealing with a general normal distribution what distribution do we usually
change it to so we can find the probability
?
A. ) the standard normal distribution
B. ) the uniform distribution
C. ) a generic discrete distribution
D. ) Any Distribution will work
_________ 6. ) A
radio station claims that the amount of advertising per hour of broadcast time
is normally distributed with an average of 3 minutes and a standard deviation
equal to 2.1 minutes. You listen to the
radio station for one hour, at a randomly selected time during the day, and
carefully observe that the amount of advertising is equal to 7 minutes. Calculate the z - score for this amount of
advertising time.
A. ) z = 1.63
B. ) z = 1.90
C. ) z = 4.00
D. ) z = - 1.90
________ 7. ) If
a fair coin is flipped twice with the outcome of each flip independent of each
other, then the probability that at least one of the two flips results in a
head is
A. )
B. ) ![]()
C. ) ![]()
D. ) 1
________ 8. ) Only
20 % of the applicants for new positions at a large software company are
female. Assuming that two positions
will be filled independently of each other, what is the probability that both
positions are filled by males ?
A. ) . 64
B. ) . 04
C. ) . 96
D. ) . 8
________ 9. ) A
large family is going shopping for a new van.
The probability that the family will purchase a Ford van is . 33 . The probability of purchasing a Chevy van is
.25. The probability of purchasing a
Dodge is .20 , and the probability of purchasing a Toyota is .22 . What is the probability the family will end
up purchasing a Ford or Chevy or Dodge van ?
A. ) .0165
B. ) .22
C. ) .78
D. ) .75
Part IV : Computational Problems
For Problems 10 - 11 use the following information :
The number of
days of sick-leave used in a year by state employees for the state of Tennessee
has a normal distribution with a mean of 9 days and a standard deviation
of 2 days.
10. ) What is the
probability that a state employee from Tennessee will use more than 13 days of
sick leave in a year ?
11. ) About 16.11
% of the state employees use fewer than how many sick leave days in a year ?
A college math
professor has surveyed her records and found the following frequency
distribution of the grades she has assigned to the 1187 students who have taken
her calculus classes.
GRADE A B C D
F
Frequency 125 352 461 187 62
12. ) What is the
probability that a randomly selected student received an A in calculus from
this professor ?
13. ) What is the
probability that two independently selected students both received an A in
calculus from this professor ?
14. ) Janice wants
to become a police officer. She must
pass a
physical exam
and then a written exam. Records show
the probability of passing the physical exam is 0.85 and that once the physical
is passed the probability of passing the written exam is 0.60. What is the probability that Janice passes
both exams ?
15. ) Given
the following probability distribution find the mean and
variance for the distribution :
for x=1,2,3 or 4 .
16. ) In
California, 30% of the people have a certain blood type.
What is the
probability that exactly 5 out of a randomly selected group of 14 Californians
will have that blood type ?
It is believed
that 58% of married couples with children agree on methods of disciplining
their children. If 200 couples are
surveyed answer the following two questions :
17. ) Find
the probability that exactly 110 couples agree.
18. ) Find
the probability that more than 100 couples agree.
19. ) Find
.
20. ) The
baggage weights for passengers using a particular airline
are normally
distributed with a mean of 20 lb and standard deviation of 4. Find the
probability that 100 passengers will have an average baggage weight of more
than 21.25 lbs.