Tuesday
October 21, 2014

Homework Help: statistics

Posted by Anand on Monday, October 17, 2011 at 7:10pm.

The Frayed Nerves Anxiety Scale (FNAS) is used to measure the anxiety level of people on a scale from 0 to 1000. Four students were randomly chosen and given the FNAS before their second exam. Their scores were 700, 653, 740, and 707. The standard deviation sigma of the test is 40.

1. What is x bar?

2. What is the standard deviation of the mean?

3. What is the 95% confidence interval for x bar?

4. What is the 99% confidence interval for x bar?

5. How many students do you need to survey to get the plus or minus for the 95% confidence interval down to 20?

6. How about for the 99% confidence interval?

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

Statistics - The Computer Anxiety Rating Scale (CARS) measures an individual's ...
statistics - The Computer Anxiety Rating Scale (CARS) measures an individuals ...
Statistics - I bemieve the t test is paired , want to make usre beofre I run the...
math - A researcher wanted to answer the following question: What is the ...
stsats - A researcher wanted to answer the following question: What is the ...
Stats - I ran this an an independent samples t-test. It is a t rest according to...
stats - Which test do you use to solve this problem One-sample or independent ...
stats - Which test do you use to solve this problem One-sample or independent ...
statistics - You are conducting an experiment to see if a given therapy works to...
psychology - in his research, Dr. Caulfiel wants compare levels of tests anxiety...

Search
Members