4.7.D—Calculate the standard error and margin of error for estimating the difference between two population means

Calculate the standard error and margin of error for estimating the difference between two population means.

• The standard error for the difference between two sample means is ss2 2 SE 1 2 xx- =+ 12 nn1 2 , where s1 and s2 are the sample standard deviations.
• For the difference between two sample means, the margin of error is the critical value (t∗) times the standard error (SE) of the difference of two sample means, which equals 2 * ss 2 t 1 + 2 nn1 2 . 135 Inference for Quantitative Data: Means UNIT 4