SOLUTION: If a thumbtack is dropped, the probability of it landing point up is .4. If 12 tacks are dropped, find the probability of at least 9 points up in fraction form

Question 585973: If a thumbtack is dropped, the probability of it landing point up is .4. If 12 tacks are dropped, find the probability of at least 9 points up in fraction form
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
If a thumbtack is dropped, the probability of it landing point up is .4. If 12 tacks are dropped, find the probability of at least 9 points up in fraction form
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Binomial Problem with n = 12; p(up) = 0.4 ; p(other) = 0.6
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P(9<= x <=12) = 1 - binomcdf(12,0.4,8) = 0.0153 = 153/10000
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Cheers,
Stan H.
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