Problem:

The following are the results of 10 attempts to measure the concentration of nitrate ions (in micrograms/mL) in a specimen of water.

0.513 0.524 0.529 0.481 0.492 0.499 0.518 0.490 0.494 0.501

a) calculate a 95% confidence interval for the true concentration.

I got sample mean= 0.5041

t= 2.262

and I am trying to fit it into the sample mean +/- margin of error equation

Thanks in advance!

Leslie