A researcher wishes to estimate the mean SAT score by computing a 95% confidence interval from a simple random sample of 12 scores. The 12 scores are 320,380,400,420,500,520,600,660,720,730,750 and 780. what is the confidence interval for the mean score? The population distribution of the SAT is approximately normal.

Question

A researcher wishes to estimate the mean SAT score by computing a 95% confidence interval from a simple random sample of 12 scores.  The 12 scores are 320,380,400,420,500,520,600,660,720,730,750 and 780.  what is the confidence interval for the mean score?  The population distribution of the SAT is approximately normal.

agent0smith · Answer

https://qph.is.quoracdn.net/main-qimg-4f058284552e79a3efa71d11c841bd7d?convert_to_webp=true x is the mean of the scores s is standard deviation of the scores n is how many scores there are z* is the z-score for 95% confidence, pretty sure it's 1.96 for 95%.

bekkah323 · Answer

It is but the standard deviation is not listed

bekkah323 · Answer

x is 565
n=12
z=1.95

agent0smith · Answer

Neither is the mean. You're supposed to work those out. Either by hand or with a calculator.

bekkah323 · Answer

how do you calculate a sample standard deviation

agent0smith · Answer

With a calculator or do it the long way by hand, Google the formula if you're doing it by hand