Posted by **Angel** on Tuesday, April 10, 2007 at 3:17pm.

data from sample of 400 cases, variable has 95% confidence interval of 54.3 to 54.7

I found the mean-

how do i find standard error- step by step please.

Standard error = sd/√n

Note: sd = standard deviation; n = sample size.

You'll need to determine the standard deviation in order to find the standard error.

I'm assuming you determined the mean to be 54.5; therefore, you can determine standard deviation using the following method.

.2 = 1.96 (sd/√400) -->.2 represents the margin of error.

Solve for standard deviation, then you will be able to determine the standard error.

I hope this will help.

## Answer this Question

## Related Questions

- statistics - A single sample is being used to construct a 90% confidence ...
- Statistics - Find the margin of error for a 95% confidence interval for ...
- Statistics - Find the margin of error for a 95% confidence interval for ...
- Math Statistics - 5. Students in an introductory statistics class were asked to ...
- statistics - A sample of 200 students in a English class were asked- How long ...
- Math - The price for 2 tickets with online service charges, large popcorn and 2 ...
- statistics - what are the mean and standard deviation of a sampling distribution...
- Statistics - It is known that the amount of time needed to change the oil in a ...
- Statistics - A random sample of forty-eight 200 meter swims has a mean of 3:12 ...
- Sampling Distribution - Sampling Distribution Complete solutions and ...