Assume that a sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the
given statistics and confidence level. Round the margin of error to four decimal places.
-90% confidence; the sample size is 1510, of which 35% are successes
A) 0.0241
B) 0.0252
C) 0.0202
D) 0.0157

Question

Quizplus · Accepted Answer

We can use the formula:

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

where z is the z-score corresponding to the confidence level, p is the sample proportion, and n is the sample size.

For a 90% confidence level, the z-score is 1.645.

Thus, E = 1.645*(sqrt(0.35*(1-0.35)/1510)) = 0.0202

Therefore, the margin of error is 0.0202 or approximately 0.0202 after rounding to four decimal places.
The answer is Choice C.

Assume That a Sample Is Used to Estimate a Population