## ← Probability of Mean - Intro to Descriptive Statistics

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Showing Revision 6 created 05/25/2016 by Udacity Robot.

1. Let's bring the z table back again. So now our z score is 2.26. So here's 2.2,
2. and here is where it intersects 0.06. So the probability of getting a mean less
3. than 40 is 0.9881. The probability of getting at least 40 is 1 minus 0.9881,
4. which is a far lower probability. So we have this really skinny sampling
5. distribution and the probability of getting greater than 40 is very small,
6. 0.0119. So getting a sample of size 250 with a mean of 40, is pretty unlikely to
7. occur by chance. In this case, this shows some kind of relationship, probably,
8. between the Bieber Tweeter, and Klout score.