SOLUTION: A random sample of 50 suspension helmets used by motorcycle riders and automobile race-car drivers was subjected to an impact test, and on 18 of these helmets some damage was obse

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Question 1091914: A random sample of 50 suspension helmets used by motorcycle riders and automobile race-car drivers was
subjected to an impact test, and on 18 of these helmets some damage was observed. Find a 96% two-sided
confidence interval on the true proportion of helmets of this type that would show damage from this test.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the best estimate of the population proportion is the sample proportion, and 18/50=0.36
half-interval is z(0.98)*sqrt (p*(1-p)/n)
=2.05* sqrt (0.36*0.64)/50); sqrt term is 0.06789, and half-interval is 0.1392
96% CI is (0.22, 0.50)