-degrees of freedom
-critical value
-margin of error e
- 95% confidence interval to estimate the difference in the population means
. Independent random samples were selected from two populations with unknown and unequal variances. The sample means, sample standard deviations, and sample sizes are shown below. Population 1 1₁ = 25 x = 20.35 $₁ = 2.1 Population 2 n₂=18 18.15 $₂ = 1.25