Question

suppose the probability distribution for X = number of jobs held during the past year for work study students at a university is as follows:

x= 0,1,2,3,4,5

f(x)=0.12, a, 0.28, 0.18, 0.06, 0.02

a. find a.

b. find the probability that a randomly selected student held three or more jobs during the past year.

c. find the cumulative distribution function.

d. find the E(X)

e. How many jobs would you expect a randomly selected student to hold in the past year?

Answer #1

What are the expected value, variance and standard deviation of
the following probability distribution?
Number of Offices
Proportion of Students p(X)
0
0.12
1
0.18
2
0.26
3
0.24
4
0.13
5
0.07
E(X)
Var(X)

Use excel to find the following please thank you!
The probability distribution of X, the number of defective tires
on a randomly selected automobile checked at a certain station is
given by the table. X 0 1 2 3 4 p(X) 0.54 0.16 0.06 0.04 0.2 Table
4: Distribution for defective tires
Find:
a. E(X)
b. E(X2)
C. σX (8) A sample of 600 Scholastic Aptitude Test (SAT) results
has mean of 500 and standard deviation of 100.

In the past year, 13% of businesses have eliminated jobs. If 7
businesses are selected at random, find the probability that at
least 4 have eliminated jobs during the last year. Round you answer
to four decimal places.
P(at least 4 have eliminated jobs during the last year) =
_________

Consider the probability distribution of the discrete random
vector [X,Y] where X represents the number of orders for chickens
in August at neighboring supermarket and Y represents the number of
orders in September. The Joint distribution is showing the
following table.
Y
51
52
53
54
55
51
0.06
0.05
0.05
0.01
0.01
52
0.07
0.05
0.01
0.01
0.01
53
0.05
0.10
0.10
0.05
0.05
54
0.05
0.02
0.01
0.01
0.03
55
0.05
0.06
0.05
0.01
0.03
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2. If two students are selected randomly what is the chance that
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*Please explain how you got your answers.
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Number of Accidents Daily (X)
P(X)
0
0.19
1
0.28
2
0.22
3
0.12
4
0.09
5
0.06
6
0.04
a. Compute the mean number of accidents per day.
μ =1.98 correct
b. Compute the standard deviation.
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σ =___________
Determine the mean and standard deviation of the variable...

The probability distribution below describes the number of
thunderstorms that a certain town may experience during the month
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Let X represent the number of thunderstorms in
August.
X 0 1 2 3
P(X) 0.1 0.3 B 0.3
Determine the value of B
What is the expected value of thunderstorms for the town each
August?
What is theVariance value of thunderstorms for the town each
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Find the Mode of this probability distribution.
Find the CDF for X (cumulative...

Suppose that the amount of time that students spend studying in
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What is the distribution of XX? XX ~ N(,)
What is the distribution of ¯xx¯? ¯xx¯ ~ N(,)
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If one randomly selected student...

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