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# Stats help - Binomial distribution?

1. Suppose a probability that a certain experiment will be successful is .4 - and let X denote the number of successes that are obtained in 15 independent performances of the experiment.

a. What is E(X)?
b. What is the Var(X)?
Find Pr(6≤X≤9)?

2. (Original post by fdsa212)
Suppose a probability that a certain experiment will be successful is .4 - and let X denote the number of successes that are obtained in 15 independent performances of the experiment.

a. What is E(X)?
b. What is the Var(X)?
Find Pr(6≤X≤9)?

You expect us to do your work!

Why are you using Pr, surely you should use capital P.

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