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Given x as a binomial random variable resulting from the performance of n Bernoulli trials with a probability of success p, determine the expected value and variance of x.

User Spagi
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Final Answer:

The expected value
(\(E[x]\)) of a binomial random variable x resulting from
\(n\) Bernoulli trials with a probability of success p is
\(E[x] = np\). The variance
(\(Var[x]\)) is given by
\(Var[x] = np(1-p)\).

Step-by-step explanation:

In a binomial distribution, where \(x\) represents the number of successes in \(n\) independent Bernoulli trials, the expected value is a measure of the center of the distribution, and the variance indicates the spread or dispersion.

1. Expected Value
(\(E[x]\)):

The expected value is calculated by multiplying the number of trials
(\(n\))by the probability of success
(\(p\)). Mathematically,
\(E[x] = np\). This formula represents the average or mean number of successes one would expect in \(n\) trials.

2. Variance
(\(Var[x]\)):

The variance of a binomial distribution is found by multiplying the number of trials n by the probability of success p and the probability of failure
(\(1-p\)) . The formula is
\(Var[x] = np(1-p)\). This quantifies the spread or variability in the distribution.

Understanding these measures is crucial for characterizing the behavior of a binomial random variable. They provide insights into the central tendency and the extent to which individual trials deviate from the expected value.

User Sorin Lica
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