It is known that the variance of a population equals 1,936. A random sample of 121 has been taken from the population. There is a .95 probability that the sample mean will provide a margin of error of
A)7.84 or less
B)31.36 or less
C)344.96 or less
D)1,936 or less

Question

Quizplus · Accepted Answer

The margin of error for a sample mean is calculated using the formula: Margin of Error = Z * (σ/√n), where Z is the Z-score for the desired confidence level (1.96 for 95%), σ is the population standard deviation (√1,936 = 44), and n is the sample size (121). Thus, Margin of Error = 1.96 * (44/√121) = 1.96 * 4 = 7.84.

It Is Known That the Variance of a Population Equals