Question 1084781
mean = 12 * 0.15 = 1.8
standard deviation is square root(12 * 0.15 * (1-0.15)) = 1.2369
:
P ( X = 4 ) = P ( X < or = 5 ) - P ( X < or = 4 )
:
z-score(5) = (5 - 1.8) / 1.2369 = 2.5871
z-score(4) = (4 - 1.8) / 1.2369 = 1.7786
:
look in table of z-values for associated probability
:
P ( X = 4 ) = 0.99516 - 0.96235 = 0.0328 approximately 0.03
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