In a survey of 280 adults over 50,80% said they were taking vitamin supplements.Find the margin of error for this survey if we want a 99% confidence in our estimate of the percent of adults over 50 who take vitamin supplements.

A) 10.5%
B) 13.8%
C) 6.16%
D) 4.69%
E) 17.2%

Question

Elizabeth Sachmacinski · Accepted Answer

Final Answer : C, Explanation :  To find the margin of error, we need to use the formula:Margin of Error = z * (sqrt(p*q/n))where p is the proportion of adults over 50 who take vitamin supplements (0.8), q is the complementary proportion (1 - 0.8 = 0.2), n is the sample size (280), and z is the z-score that corresponds to the desired level of confidence (99%).Using a z-score calculator, we find that the z-score for a 99% confidence level is approximately 2.576.Substituting the values into the formula, we get:Margin of Error = 2.576 * (sqrt(0.8*0.2/280)) = 0.0616 or 6.16%Therefore, the best choice is C, with a margin of error of 6.16%.

In a survey of 280 adults over 50,80% said they were taking vitamin supplements.Find the margin of error for this survey if we want a 99% confidence in our estimate of the percent of adults over 50 who take vitamin supplements.

A) 10.5%
B) 13.8%
C) 6.16%
D) 4.69%
E) 17.2%

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In a survey of 280 adults over 50,80% said they were taking vitamin supplements.Find the margin of error for this survey if we want a 99% confidence in our estimate of the percent of adults over 50 who take vitamin supplements.A) 10.5%B) 13.8%C) 6.16%D) 4.69%E) 17.2%

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In a survey of 280 adults over 50,80% said they were taking vitamin supplements.Find the margin of error for this survey if we want a 99% confidence in our estimate of the percent of adults over 50 who take vitamin supplements.

A) 10.5%
B) 13.8%
C) 6.16%
D) 4.69%
E) 17.2%