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Q1. | X and Y are two random variable and Z = X + Y. Let σ_{x}^{2}, σ_{y}^{2} and σ_{z}^{2} be variance of X, Y and Z. Then |

A. | σ_{z}^{2} = σ_{x}^{2} + σ_{y}^{2} [Correct Answer] |

B. | σ_{z}^{2} ≤ σ_{x}^{2} + σ_{y}^{2} [Wrong Answer] |

C. | σ_{z}^{2} < σ_{x}^{2} + σ_{y}^{2} [Wrong Answer] |

D. | σ_{z}^{2} > σ_{x}^{2} + σ_{y}^{2} [Wrong Answer] |

View Answer
Explanation:-
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