Question

Find the mean of the following probability distribution:

X= xi:	1	2	3
P(X= xi) :	\[\frac{1}{4}\]	\[\frac{1}{8}\]	\[\frac{5}{8}\]

 

Answer 1

xi	pi	pixi
1	\[\frac{1}{4}\]	\[\frac{1}{4}\]
2	\[\frac{1}{8}\]	\[\frac{2}{8}\]
3	\[\frac{5}{8}\]	\[\frac{15}{8}\]

Mean = \[\sum\nolimits_{}^{}\] p_ix_i = \[\frac{1}{4} + \frac{2}{8} + \frac{15}{8} = \frac{2 + 2 + 15}{8} = \frac{19}{8}\]