Question:
If X is a random variable with E(X) = 6 and V(X) = 3, then E(X2) is equal to
If X is a random variable with E(X) = 6 and V(X) = 3, then E(X2) is equal to
Updated On: Apr 4, 2025
- 33
- 36
- 39
- 42
- 27
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The Correct Option is C
Solution and Explanation
We are given the following information:
- \( E(X) = 6 \)
- \( V(X) = 3 \)
We can use the formula for variance:
\[ V(X) = E(X^2) - (E(X))^2 \]
Substitute the given values:
\[ 3 = E(X^2) - (6)^2 \] \[ 3 = E(X^2) - 36 \]
Now solve for \( E(X^2) \):
\[ E(X^2) = 3 + 36 = 39 \]
Answer: 39
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