<PRE><B>Question 959161</B>
if the probability of getting a lift to work on any morning is 0.6 .X is the number of days in a working week of 5 days
 (a) what is the probability distribution of X? (please justify)
mean = np = 5*0.6 = 3
std = sqrt(npq) = sqrt(3*0.4) = sqrt(1.2)
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 (b) what is the probability that in a working week will get a lift only twice?
P(x = 2) = 5C2*0.6^2*0.4^3 = binompdf(5,0.6,2) = 0.2304
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Cheers,
Stan H.
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