If the Probability Distribution of a Random Variable X is Given by Write the Value Of K. X = Xi : 1 2 3 4 P (X = Xi) : 2k 4k 3k K - Mathematics

Question

If the probability distribution of a random variable X is given by Write the value of k.

X = x_i :	1	2	3	4
P (X = x_i) :	2k	4k	3k	k

Sum

Solution

We know that the sum of probabilities in a probability distribution is always 1.

∴ P (X = 1) + P (X = 2) + P (X = 3) + P (X = 4) = 1
$\Rightarrow 2 k + 4 k + 3 k + k = 1$
$\Rightarrow 10 k = 1$
$\Rightarrow k = \frac{1}{10} = 0.1$

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Random Variables and Its Probability Distributions

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Chapter 32: Mean and Variance of a Random Variable - Very Short Answers [Page 45]

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Chapter 32 Mean and Variance of a Random Variable
Very Short Answers | Q 4 | Page 45

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If the Probability Distribution of a Random Variable X is Given by Write the Value Of K. X = Xi : 1 2 3 4 P (X = Xi) : 2k 4k 3k K - Mathematics

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