A media rating company that publishes television ratings uses a random sample of 1600 households and _nds that 20% watched a particular show in a given week. What is the approximate margin of error?

Question

A media rating company that publishes television ratings uses a random sample of 1600 households and _nds that 20% watched a particular show in a given week. What is the approximate margin of error?

Answer 1

the sample size is 1600 and the percentage for the target show is 20%

The mean = sample size times percentage. μ = 1600 times 0.20

μ = 320

The standard deviation = the square root of μ times (1-.20).

Sigma = square root of 320(0.8)

Sigma = 16

Typically go for a confidence level of 5% or 2 sigma.or in this case plus or minus 32.

32/1600 = 0.02 or 2%

Our margin of error is plus or minus 2%.