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In a binomial distribution, the mean is  and variance is . What is the probability that random variable D = 2?

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Concept:

For the binomial distribution of probability

  • Mean = np
  • Variance = npq

Where n is the total number of cases, p is probability of favorable cases and q is probability of unfavorable cases(1 - p)

Calculation:

Given mean = np =  and variance = npq = 

 = 

q = 

p = 1 - q = 

np = 

n = 4

∴ The probability that random variable D = 2

P = 

P = 

P = 

P = 

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