Suppose an advertising agency is conducting a survey concern

Suppose an advertising agency is conducting a survey concerning the effectiveness of commercials during the Super Bowl. If 30% of people watch the Super Bowl, and if the agency contacts 150 people what is the probability that at least 35% people that watched the game? (please round your answer to 4 decimal places)

Solution

P( p > 0.35 )

P( z > [ 0.35 - 0.30 ] / srqt[ 0.30*0.70 / 150 ] )

P( z > 0.05 / 0.037 )

P( z > 1.35 )

using tables of normal distribution Z we have

P( z > 1.35) = 0.0885