Question 825848: Suppose an advertising agency is conducting a survey concerning the effectiveness of commercials during the Super Bowl. If 31% of people watch the Super Bowl, and if the agency contacts 180 people, what is the probability that less than 25% of people that watched the game?
Here's what I've come up with so far (it's not much)
n=180
A success would be 24
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Suppose an advertising agency is conducting a survey concerning the effectiveness of commercials during the Super Bowl.
If 31% of people watch the Super Bowl, and if the agency contacts 180 people, what is the probability that less than 25% of people that watched the game?
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z(0.25) = (0.25-0.31)/sqrt[0.31*0.69/180] = -1.7405
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P(x < 0.25) = P(z < -1.7405) = normalcdf(-100,-1.7405) = 0.0409
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Cheers,
Stan H.
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