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प्रश्न
Mark the correct alternative in the following question:
For the following probability distribution:
| X : | 1 | 2 | 3 | 4 |
| P(X) : |
\[\frac{1}{10}\]
|
\[\frac{1}{5}\]
|
\[\frac{3}{10}\]
|
\[\frac{2}{5}\]
|
The value of E(X2) is
पर्याय
3
5
7
10
उत्तर
The probability distribution of X is given below:
| X : | 1 | 2 | 3 | 4 |
| P(X) : |
\[\frac{1}{10}\]
|
\[\frac{1}{5}\]
|
\[\frac{3}{10}\]
|
\[\frac{2}{5}\]
|
\[E\left( X^2 \right) = 1^2 \times \frac{1}{10} + 2^2 \times \frac{1}{5} + 3^2 \times \frac{3}{10} + 4^2 \times \frac{2}{5}\]
\[ = \frac{1}{10} + \frac{8}{10} + \frac{27}{10} + \frac{64}{10}\]
\[ = \frac{100}{10}\]
\[ = 10\]
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