Mathematical Methods · Unit 3 · Discrete random variables · General discrete random variables
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A discrete random variable \( X \) represents the number of defective components in a batch. The probability distribution of \( X \) is shown in the table. (a) Calculate \( E(X) \). (b) Calculate \( E(X^2) \). (c) Determine the standard deviation of \( X \).
A technology company monitors the number of network outages per week. The probability distribution for \(X\), the number of outages in a randomly selected week, is shown in the table below. Determine the standard deviation of \(X\).
A discrete random variable $X$ represents the number of defective items found in a batch of 20 items inspected at a factory. The probability distribution of $X$ is shown in the table below. Determine the standard deviation of $X$, giving your answer correct to 2 decimal places.