SOLUTION: Sixty five percent of 12th graders attend school in a particular urban district. If a sample of 450 12th grade children is selected. 1. Find the probability that at least 290 a

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Question 1121524: Sixty five percent of 12th graders attend school in a particular urban district. If a sample of 450 12th grade children is selected.
1. Find the probability that at least 290 are actually enrolled in the school
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
find mean and sd of the distribution
mean=np=450*0.65 or 292.5
variance is np(1-p) or 292.5*0.35 =102.375
sd is sqrt (V) or 10.02
z>(289.5-292.5)/10.02, using continuity correction factor of -0.5 to have z at least 290
z>-0.2994
probability is 0.6177