Answer: 0.8588
Step-by-step 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
