Download App

Mean and variance of a random variable — Maths STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceMathsMean and variance of a random variable1 Mark
MCQ
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
    $16$
  • ✓
    $32$
  • D
    $48$
✓

Answer

Correct option: C.
$32$
$\sum\limits_2^5\text{P}(\text{x})=1$
$\frac{5}{\text{k}}+\frac{7}{\text{k}}+\frac{9}{\text{k}}+\frac{11}{\text{k}}=1$
$\text{k}=32$
NOTE: Question is modified.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "MCQ" from Mean and variance of a random variable→Mean and variance of a random variable — all question types→Maths STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

Objective function of a $\text{LPP}$ is:
→
If $\bar{a} \bar{b} \bar{c}$ are non coplanar unit vectors such that $\bar{a} \times(\bar{b} \times \bar{c})=\frac{(\bar{b}+c)}{\sqrt{2}}$ then the angle

between $\bar{a}$ and $\bar{b}$ is

→
A line passes through two points $A (2,-3,-1)$ and $B (8,-1,2)$. The co-ordinates of a point on this line nearer to the origin at a 14 units from A are
→
Equation of plane parallel to plane $2 x+4 y+2 z=5$ and passing through the point $(1,2,3)$ is
→
$\big(\vec{\text{a}}+\vec{\text{b}}\big).\big(\vec{\text{b}}+\vec{\text{c}}\big)\times\big(\vec{\text{a}}+\vec{\text{b}}+\vec{\text{c}}\big)=$
→
If the function $f : R \rightarrow A$ given by $\text{f(x)}=\frac{\text{x}^2}{\text{x}^2+1}$ is a surjection, then $A =$
→
If $2\bar{a}$$+\bar{b}$$=3 \overline{ c }$, then A divides BC in the ratio
→
Side of an equilateral triangle expands at the rate of $2\text{cm}/ \text{sec}.$ The rate of increase of its area when each side is $10\ cm$ is:
→
If $x^y=y^{ x }$, then $\frac{d y}{d x}=$
→
A bag contains 4 red and 3 black balls. One ball is drawn and then replaced in the bag and the process is repeated. Let $X$ denote the number of times black ball is drawn in 3 draws. Assuming that at each draw each ball is equally likely to be selected, then the probability distribution of $X$ is given by
→