Question 1 - A-Level Maths

Exam Board	OCR
Module	S1 (Statistics 1)
Year	2007
Session	June
Topic	Discrete Probability Distributions
Type	Calculate E(X) from given distribution

1 The table shows the probability distribution for a random variable X.

x	0	1	2	3
\(\mathrm { P } ( \mathrm { X } = \mathrm { x } )\)	0.1	0.2	0.3	0.4

Calculate \(\mathrm { E } ( \mathrm { X } )\) and \(\operatorname { Var } ( \mathrm { X } )\).