Question

Suppose a sample of 256 was taken from a population with a standard deviation of 96 centimeters. What is the margin of error for a 68% confidence interval?
A. 4
B. 8
C. 10
D. 6

Answer 1

Answer:

D. 6

Step-by-step explanation:

Here we are given that a sample of 256 was taken from a population with a standard deviation of 96 centimeters i.e. $\sigma$ = 96 and n = 256.

And we have to calculate the margin of error for a 68% confidence interval.

Firstly from z score% table we observe that at 32% level of significance the z score critical value is given by 0.99744 .

And Margin of error formula is given by ;

                        $Z_\frac{\alpha}{2}$ * $\frac{\sigma}{\sqrt{n} }$ = 0.99744 * $\frac{96}{\sqrt{256} }$ = 5.98

Approximately, we get Margin of error = 6.