(a)
The marginal probability distribution of refrigerator.
(a)
Explanation of Solution
The probability distribution of refrigerator and stoves sold daily is shown below:
Table 1
Stoves | Refrigerator | ||
0 | 0 | 2 | 3 |
1 | 0.08 | 0.14 | 0.12 |
2 | 0.09 | 0.17 | 0.13 |
0.05 | 0.18 | 0.04 |
The marginal probability of refrigerator sold daily is shown below:
Table 2
Refrigerator X | P(x) |
0 | 0.22 |
1 | 0.49 |
2 | 0.29 |
Probability distribution: The probability distribution shows the probabilities of incidence of different likely outcomes in a test.
(b)
The marginal probability distribution of stoves.
(b)
Explanation of Solution
The marginal probability of stoves sold daily is shown below:
Table 3
Stoves Y | P(y) |
0 | 0.34 |
1 | 0.49 |
2 | 0.27 |
(c)
The means and variance of refrigerator.
(c)
Explanation of Solution
The mean value of the probability distribution of refrigerator is calculated as follows:
The mean value is 1.07.
The variance of the probability distribution of refrigerator is calculated as follows:
The variance is 0.505.
(d)
The mean and variance of stoves.
(d)
Explanation of Solution
The mean value of the probability distribution of stoves is calculated as follows:
The mean value is 0.93.
The variance of the probability distribution of stoves is calculated as follows:
The variance is 0.605.
(e)
Calculate covariance and the coefficient of correlation.
(e)
Explanation of Solution
Covariance and the coefficient of correlation are calculated as follows:
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Chapter 7 Solutions
Statistics for Management and Economics (Book Only)
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