Question

Assume a binomial probability distribution with n=55 and π=0.34 . Compute the following: (Round all your z values to 2 decimal places.) The mean and standard deviation of the random variable. (Round your "σ" to 4 decimal places and mean to 1 decimal place.) The probability that X is 22 or more. (Use the rounded values found above. Round your answer to 4 decimal places.) The probability that X is 14 or less. (Use the rounded values found above. Round your answer to 4 decimal places.)

Answer 1

Answer: 0.8588

Explanation:

Assume a binomial probability distribution with n = 40 and (symbol looks like a pie sign) = 0.55.

Compute the following: (Round the value for standard deviation and intermediate calculations to 2 decimal places and your final answer to 4 decimal places.)

The mean and standard deviation of the random variable.

mean = np = 40*0.55 = 22

std = sqrt(npq) = sqrt(22*0.45) = 3.1464

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The probability that X is 25 or greater.

P(25<= x <= 40) = 1 - binomcdf(40,0.55,24) = 0.2142

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The probability that X is between 15 and 25, inclusive.

P(15<= x <=25) = binomcdf(40,0.55,25)-binomcdf(40,0.55,14) = 0.8588