diff --git a/education/statistics/Sampling.md b/education/statistics/Sampling.md
index 823b6cc..65d2ef9 100644
--- a/education/statistics/Sampling.md
+++ b/education/statistics/Sampling.md
@@ -77,4 +77,9 @@ This equation should be a review:
 $$ SE_{ave} = \frac{SD}{\sqrt{size\space samp}} $$
 The above equation will give you an interval that you can be 95% confident that the true random will be within that point.
 
-95% does *not* mean that 95% of the data is in the interval, it just means we are 95% confident that the actual point is going to lie within the range specified.
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+95% does *not* mean that 95% of the data is in the interval, it just means we are 95% confident that the actual point is going to lie within the range specified.
+
+A confidence interval is only valid if the sample is not a simple random sample.
+
+If we're using two standard deviations, the below statement can be used:
+"We can be 95% confident that the interval \[we have constructed] contains the true average \[thing being measured]."
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