10.03 Centre and spread of discrete random variables

Interactive practice questions

Consider the table.

$x$`x`	$0$0	$1$1	$2$2	$3$3	$4$4
$P$`P`$($($X=x$`X`=`x`$)$)	$0.1$0.1	$0.45$0.45	$0.15$0.15	$0.05$0.05	$0.25$0.25

Does the table represent a discrete probability distribution?

Yes

What is the most likely outcome for the random variable $X$X?

Calculate $E\left(X\right)$E(X).

Easy

2min

Consider the probability distribution table shown for the random variable $X$X.

Easy

1min

Consider the probability distribution shown.

Easy

1min

Consider the probability distribution table shown for the random variable $X$X.

Easy

1min

use relative frequencies obtained from data to determine point estimates of probabilities associated with a discrete random variable

recognise uniform discrete random variables and use them to model random phenomena with equally likely outcomes

recognise the mean or expected value of a discrete random variable as a measurement of centre, and evaluate it in simple cases

recognise the variance and standard deviation of a discrete random variable as a measure of spread, and evaluate these in simple cases

use discrete random variables and associated probabilities to solve practical problems