SOLUTION: Please help! 4% of Americans surveyed lie frequently. Suppose you conduct a survey of 450 college students and find that 22 of them lie frequently. Compute the probability that,

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Question 388231: Please help!
4% of Americans surveyed lie frequently. Suppose you conduct a survey of 450 college students and find that 22 of them lie frequently. Compute the probability that, in a random sample of 450 students, at least 22 lie frequently, assuming the true percentage is 4%.
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Use the normal approximation to the binomial distribution, with mu+=+np+=+450%2A0.04+=+18, and sigma+=+sqrt%28npq%29+=+sqrt+%28450%2A0.04%2A0.96%29+=+4.156922. Then
. Hence P%28X+%3E=+21.5%29+=+P%28Z+%3E=+0.842%29. Now just use any standard normal distribution table to find P%28Z+%3E=+0.842%29 and hence the answer you want.