Posted by Kim on .
Find the 98% confidence interval for estimating ìd based on these paired data and assuming normality. (Give your answers correct to one decimal place.)
Before
68,58,64,62,58,67
After
40,42,46,37,45,38
Lower limit:
Upper limit:

STATs 353 
MathGuru,
You'll need to start by finding a confidence interval for 2 samples.
Here is one you might be able to use:
CI = (mean difference) ± tvalue (standard deviation difference/√n)
You will need to calculate the means and standard deviations.
Tvalue is found using a ttable for 98% confidence.
n = sample size
Once you have the interval calculated, you will have the lower and upper limits.