<PRE><B>Question 345069</B>
from past experience, the pass rate of students has been 70%. if 8 students are randomly selected.
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Binomial Problem with n = 8 and p = 0.7
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a) what is the probability at least half will fail?
P(4&lt;= x &lt;=8) = 1-binomcdf(8,0.7,3) = 0.9420
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b) what is the standard deviation of the distribution?
std = sqrt(npq) = sqrt(8*0.7*0.3) = 1.2961
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c)what is the probability that no student will fail?
P(x = 0) = 0.7^8 = 0.0576
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d) state the name given to the probability distribution being described in the question and state one of its characteristics?
binomial; n independent trials.
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Cheers,
Stan H.</PRE>