MCQ
Choose the correct answer from the given four options.
The probability distribution of a discrete random variable X is given below:
$\text{X}$
$2$
$3$
$4$
$5$
$\text{P}(\text{X})$
$\frac{5}{\text{k}}$
$\frac{7}{\text{k}}$
$\frac{9}{\text{k}}$
$\frac{11}{\text{k}}$
The value of k is:
  • A
    8.
  • B
    16.
  • C
    32.
  • D
    48.

Answer

  1. 32.

Solution:

We know that, $\sum\text{P}\text{X}=1$

$\Rightarrow\frac{5}{\text{k}}+\frac{7}{\text{k}}+\frac{9}{\text{k}}+\frac{11}{\text{k}}=1$

$\Rightarrow\frac{32}{\text{k}}=1$

$\therefore\text{k}=32$

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