Question 996845
P(x=2)=15C2(0.3)^2(0.7)^13=105*(0.09)(0.009688)
without rounding until the end, that is 0.0916
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P (x>=8)  Use the table.  The cumulative probability through x=7 is 0.95, so the probability of >=8 is 0.05.
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E(x)=np=15*0.3=4.5
variance is np(1-p)=15(0.3)(0.7)=3.15
sd=1.77