SOLUTION: please help...i've done several problems but i'm stuck on a couple... Suppose that 30% of the vehicles in a mall parking lot belong to emplyees. Nine vehicles are chosen at rando

Algebra ->  Probability-and-statistics -> SOLUTION: please help...i've done several problems but i'm stuck on a couple... Suppose that 30% of the vehicles in a mall parking lot belong to emplyees. Nine vehicles are chosen at rando      Log On


   



Question 322068: please help...i've done several problems but i'm stuck on a couple...
Suppose that 30% of the vehicles in a mall parking lot belong to emplyees. Nine vehicles are chosen at random. find the probability that:
exactly 3 belong to mall employees
at most 3 belong to mall employees
at least 7 belong to mall emplyees

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose that 30% of the vehicles in a mall parking lot belong to emplyees.
Nine vehicles are chosen at random.
find the probability that:
exactly 3 belong to mall employees = 9C3*0.3^3*0.7^6 = 0.2668
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at most 3 belong to mall employees = binomcdf(9,0.3,3) = 0.7297
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at least 7 belong to mall emplyees = 1 - binomcdf(9,0.3,6) = 0.0043
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Cheers,
Stan H.