CAIE A Level Mathematics 9709 · Discrete random variables

Discrete random variables: calculation question

2 marksFoundation

The discrete random variable $X$ has the following probability distribution, where $p$ is an unknown probability:

$x$	1	2	3
$\mathrm{P}(X = x)$	$1/10$	$2/10$	$p$

Find the value of $p$ .

(a)
Find $p$ .
[2]

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Discrete random variables: calculation question

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