Into to Statistics Jeopardy

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Into to Statistics Jeopardy
Probability Distn
Probability
100
100
200
200
300
300
400
400
500
500
600
600
Credits
2
Probability - 100

Which of the following is not a valid
probability a.) 2/3 b.) 1/8 c.) .70 d.)
5/4
Answer
3
Probability - 200
On a multiple choice test with four possible
answers for each question, what is the
probability of answering a question correctly if
you make a random guess? a.) ¼ b.) ¾ c.)
½ d.) 1
Answer
4
Probability - 300
A bag contains 4 red marbles, 3 blue marbles, and
5 green marbles. If a marble is randomly
selected, what is the probability that it is
blue? a.) 1/4 b.) 1/3 c.) 1/5 d.) 1/9
Answer
5
Probability - 400
If a person is randomly selected, find the
probability that his or her birthday is in May.
Ignore leap years. a.) 31/365 b.) 1/31 c.)
1/365 d.) 1/12
Answer
6
Probability - 500
An assignment of probability must obey which of
the following? a) The probability of any event
must be a number between 0 and 1, inclusive. b)
The sum of all the probabilities of all
outcomes in the sample space must be
exactly 1. c) The probability of an event is
the sum of the outcomes in the sample space which
make up the event. d) All of the above. e) A and
B only.
Answer
7
Probability - 600
A class consists of 61 students, 10 of which are
women. If a student is chosen at random, what is
the probability that the student is not a
women? a.) 10/61 b.) 1/61 c.) 51/61 d.)
10/51
Answer
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Probability - 100 Answer
Which of the following is not a valid
probability d.) 5/4 Probabilities are
always a value between zero and 1 inclusive.
Since 5/4 is greater than 1, it cannot be a valid
probability.
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Probability - 200 Answer
On a multiple choice test with four possible
answers for each question, what is the
probability of answering a question correctly if
you make a random guess? a.) ¼ The numerator
in our fraction indicates the number of correct
choices, the denominator is the total number of
choices.
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Probability - 300 Answer
A bag contains 4 red marbles, 3 blue marbles, and
5 green marbles. If a marble is randomly
selected, what is the probability that it is
blue? a.) 1/4 There are 3 blue marbles out of a
total of 12 marbles, so the probability of
drawing a blue marble is 4/12 which reduces to
1/4
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Probability - 400 Answer
If a person is randomly selected, find the
probability that his or her birthday is in May.
Ignore leap years. a.) 31/365 There are 31
days in May out of 365 possible birthdays.
(Note since not all months have the same number
of days, we must use days instead of months to
find the probability.)
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Probability - 500 Answer
An assignment of probability must obey which of
the following? a) The probability of any event
must be a number between 0 and 1, inclusive. b)
The sum of all the probabilities of all
outcomes in the sample space must be
exactly 1. c) The probability of an event is
the sum of the outcomes in the sample space which
make up the event. d) All of the above. a, b,
and c are all true statements
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Probability - 600 Answer
A class consists of 61 students, 10 of which are
women. If a student is chosen at random, what is
the probability that the student is not a
women? c.) 51/61 If there are 61 students,
10 of which are women, then there must be 51
(61-10) which are not women. So the probability
of not selecting a woman is 51/61
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Probability Distn - 100
Determine whether the following is a valid
probability distribution
X 1 2 3 4
P(x) 0.037 0.200 0.444 0.296
a.) Yes b.) No
Answer
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Probability Distn - 200
Determine whether the following is a valid
probability distribution
X 0 1 2 3 4 5
P(x) 0.129 0.312 -0.094 0.084 0.192 0.375
a.) Yes b.) No
Answer
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Probability Distn - 300
In a certain town, 60 of adults have a college
degree. The accompanying table describes the
probability distn for the number of adults (among
4 randomly selected adults) who have a college
degree
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
Find the probability that there are at least 2
with college degrees.
a.) 0.3456 b.) 0.8208 c.) 0.4752 d.) 0.5248
Answer
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Probability Distn - 400
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
Find the probability that there are less than 3
people who have college degrees.
a.) 0.3456 b.) 0.8704 c.) 0.5248 d.) 0.1296
Answer
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Probability Distn - 500
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
Find the expected number (the mean number) of
people with college degrees from 4 randomly
chosen people.
Answer
19
Probability Distn - 600
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
Find the standard deviation for the number of
people who have college degrees out of 4 randomly
selected people
Answer
20
Probability Distn - 100 Ans.
Determine whether the following is a valid
probability distribution
X 1 2 3 4
P(x) 0.037 0.200 0.444 0.296

• b.) No
• 0 P(x) 1This condition is met
• ? P(x) 1 The sum of the probabilities .977
  which ? 1---so this condition is not met and the
  distn is not valid

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Probability Distn - 200 Ans.
Determine whether the following is a valid
probability distribution
X 0 1 2 3 4 5
P(x) 0.129 0.312 -0.094 0.084 0.192 0.375

• b.) No
• 0 P(x) 1This condition is not met and the
  distn is not valid
• ? P(x) 1 The sum of the probabilities 1

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Probability Distn - 300 Ans.
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
Find the probability that there are at least 2
with college degrees.
b.) 0.8208
The probability of at least 2 having college
degrees is found by finding the sum of 2, 3, and
4 having degrees
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Probability Distn - 400 Ans.
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
Find the probability that there are less than 3
people who have college degrees.
c.) 0.5248
The probability of less than 3 people having
college degrees is found by finding the sum of 2,
1, and 0 having degrees .0256.1536.3456
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Probability Distn - 500 Ans.
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
To find the expected value (the mean) of the
distribution µx ? x P(x) 0(.0256)
1(.1536) 2(.3456) 3(.3456)
4(.1296) 2.4 TI-Tips Xs in list 1 P(x) in
list 2 1-var stats L1, L2
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Probability Distn - 600 Ans.
X 0 1 2 3 4
P(x) 0.0256 0.1536 0.3456 0.3456 0.1296
To find the standard deviation sv?(x-µ)2P(x)
(0-2.4)2.0256 (1-2.4)2.1536 (2-2.4)2.3456
(3-2.4)2.3456 (4-2.4)2.1296 .9798
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Credits
Questions have come from the Test Bank for Basic
Practice of Statistics And Essentials of
Statistics