(Enter your answer as a number accurate to 4 decimal places.)

Question

In a recent year, the Better Business Bureau settled 75% of complaints they received. You have been hired by the Bureau to investigate complaints this year involving computer stores. You plan to select a random sample of complaints to estimate the proportion of complaints the Bureau is able to settle. Suppose your sample size is 295. What is the probability that the sample proportion will be at most 5 percent more than the population proportion?

 (Enter your answer as a number accurate to 4 decimal places.)

Answer 1

want to find P(phat - p) < 0.05

z = (phat - p)/sqrt(p*(1-p)/n)

z = (0.05)/(0.75*0.25/295) = 1.98

P(z < 1.98) = 0.9761