For the binomial random variable , the mean and variance are:
Answer and explanation
Correct answer: B. mean 6 and variance 4.2
- Step 1: For a binomial, .
- Step 2: The variance is .
Answer
mean 6 and variance 4.2.
Why not the others: is the mean of the failures; swapping the values mixes up the formulas; and ignore .
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