Hello :D

I need some help with my statistics homework assignment. The question is... The number of suits sold per day at a retail store is shown in the table, with the corresponding probabilities

Number if suits sold, X 19 20 21 22 23
Probability, P(X) 0.2 0.2 0.3 0.2 0.1


Could someone please teach me how to find the mean, variance, and standard deviation of this data?

Thank you

Yes, it's easy. This is a "discrete non-binomial distribution".

Code:

---


  x        P(x)
-------------------
 19          .2
 20          .2
 21          .3
 22          .2
 23          .1

---

For the mean:



That is, multiply the x by its P and add them up.

Variance:



Once you have your mean, subtract it from each x, square it, multiply by its probability. Add them all up.

standard deviation:



Let me know what you get and we can check it.