# 10.27: Introduction to Inference for a Difference in Two Population Means

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## What you’ll learn to do: Conduct a hypothesis test or construct a confidence interval to investigate a difference between two population means. Interpret results in context.

In the last section we learned about a hypothesis test for a population mean. We will build on this and learn to conduct a hypothesis test about a difference between two population means and state a conclusion in context under appropriate conditions. We will then construct a confidence interval to estimate a difference in two population means (when conditions are met) and interpret the confidence interval in context.