SOLUTION: Suppose that at a large university 30% of students are involved in intramural sports. If we randomly select 20 students from this university, what is the probability that more tha

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Question 1143537: Suppose that at a large university 30% of students are involved in intramural sports. If we randomly select 20 students from this university, what is the probability that more than 7 of these students are involved in intramural sports?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Use normal approximation
mean is np=.30*20=6
variance is np(1-p)=6*0.70=4.2
sd is sqrt (V)=2.05
greater than 7 using continuity correction factor of 7.5
z>(7.5-6)/2.05 or z> 0.73
0.2327 is probability
calculator gives 0.2277 for exact answer.